I want a new and more powerful (non-Apple) wireless router but I still want to use my existing Time Capsule to continue with my Time Machine backups and I still need the Time Capsule's Network Attached Storage (NAS) features and capabilities

Question

THE SHORTER STORY
My goal is to successfully use my existing Time Capsule (TC) with a new and more powerful wireless router. I need a new and more powerful wireless router in order to reach a distant Denon a/v receiver that is physically located in a master bedroom some 50 feet away from my modem. I need to provide this Denon a/v receiver with an Internet connection so that it can obtain its firmware updates and I need to connect this Denon a/v receiver to my network in order to use its AirPlay feature. I believe l still need the TC's Network Attached Storage (NAS) features because I am not sure if the new wireless router will provide me with the NAS like features / capabilities I need to share files between my two Apple laptops with OS X 10.8.2. And I know that I absolutely need my TC's seamless integration with Apple's Time Machine (TM) application in order to continue to make effortless backups of my two Apple laptops. To my knowledge nothing works with TM like Apple's TC. I also need the hard disk storage space built into the TC.
I cannot use a long wired Ethernet cable connection in this apartment and I cannot use power-line adapters. I have read that wireless range extenders and repeaters are difficult to successfully set-up and that they will reduce data speeds, especially so when incorrectly set-up. I cannot relocate my modem and/or primary base station wireless router.
In short, I want to use my TC with my new and more powerful wireless router. I need to stop using the TC to connect to the modem. However, I still need the TC for seamless TM backups. I also need to use the TC's built in hard drive for storage. And I may still need the TC's NAS capabilities to share files wirelessly between laptops because I am assuming the new wireless router will not provide NAS capabilities for OS X 10.8.2 (products like this/non-Apple products rarely seem to work with OS X 10.8.2/Macs to provide NAS features and capabilities). Finally, I want to continue to use my Apple laptop and AirPlay to wirelessly access and play my iTunes music collection stored on the TC's hard drive. I also want to continue to use my Apple laptop, AirPlay and Apple TV to wirelessly watch movies and TV shows stored on the additional external hard drive connected to the TC via USB. Can someone please advise on how to set-up my new Asus wireless router with my existing TC in such a way to accomplish all of this?
What is the best configuration or set-up to accomplish my above goals?
Thank you in advance for your assistance!!!
THE FULL STORY
I live in an apartment building where my existing Time Capsule (TC) is located in my living room and serves many purposes. Specially, my TC is at least all of the following:
(1) Wi-Fi router connected to Comcast Internet service via Motorola SB6121 cable modem - currently the TC is the Wi-Fi base station that connects to the modem and has the gateway address to the Internet. The TC now provides the DHCP service for the Wi-Fi network.
(2) Wireless router providing Internet and Wi-Fi network access to several Wi-Fi clients - two Apple laptop computers, an iPod touch, an iPad and an iPhone all connect wirelessly to the Internet via the TC.
(3) Wired Ethernet router providing Internet and Wi-Fi network access to three different devices - a Panasonic TV, LG Blu-Ray player and an Apple TV each use one of the three LAN ports on the back of the TC to gain access to the Internet.
(4) Primary base station in my attempt to extend my wireless network to a distant (located far away) Denon a/v receiver requiring a wired Ethernet connection - In addition to the TC, which is my primary base station, I am also using a second extended Wi-Fi base station (a Netgear branded product) to wirelessly extend my WiFi network to a Denon receiver located in the master bedroom and requiring a wired Ethernet connection. I cannot use a wired Ethernet connection to continuously travel from the living room to the master bedroom. The distance is too great as I cannot effectively hide the Ethernet cable in this apartment.
(5) Time Machine (TM) backup facilitator - I use my TC to wirelessly back-up two Apple laptops using Apple's Time Machine (TM) application. However, I ran out of storage space on my TC and therefore added external storage to it. Specifically, I added an external hard drive to my TC via the USB port on the back of the TC. I now use this added external hard drive connected to the TC via USB as the destination storage drive for my TM back-ups. I have partitioned the added external hard drive, and each of the several partitions all have enough storage space (e.g., each of the two partitions used by TM are sized at three times the hard drive space of each laptop, etc.). Everything works flawlessly.
(6) Network Attached Storage (NAS) - In addition to using the TC's Network Attached Storage (NAS) capabilities to wirelessly back-up two Apple laptops via TM, I also store other additional files on both (A) the hard drive built into the TC and (B) the additional external hard drive connected to the TC via USB (there are additional separate partitions on this drive for these other additional and non-TM backup files).
I use the TC's NAS feature with my Apple laptop and AirPlay to wirelessly access and play my iTunes music collection stored on the TC's hard drive. I also use my Apple laptop, AirPlay and Apple TV to wirelessly watch movies and TV shows stored on the additional external hard drive connected to the TC via USB. Again, everything works wirelessly and flawlessly. (Note: the Apple TV is connected to the network via Ethernet and a LAN port on the back of the TC).
The issue I am having is when I try to listen to music via Apple's AirPlay in the master bedroom. This master bedroom is located at a distance of two rooms away from the TC's current location in the living room, which is a distance of about 50 feet. This apartment has a long rectangular floor plan where each room is connected to the next in a straight line. In order to use AirPlay in the master bedroom I am using a second extended Wi-Fi base station (a Netgear branded product) to wirelessly extend my WiFi network to a Denon receiver located in the master bedroom and requiring a wired Ethernet connection. This additional base station connects wirelessly to the WiFi network provided by my TC and then gives my Denon receiver the wired Ethernet connection it needs to use AirPlay. I have tried moving my iTunes music directly onto my laptop's hard drive, and then I used AirPlay on this same laptop to connect to the Denon receiver. I always get a successful connection and the song plays, but the problem is that the connection inevitably drops.
I live in an apartment building and all of the many wireless routers in this building create a great deal of WiFi interference on both the 2.4 GHz and 5GHz bands. I have tried connecting the Netgear product to each the 2.4 and 5 GHz bands, but neither band can successfully maintain a wireless connection between the TC and the Netgear product. I also attempted to maintain a wireless connection to an iPod touch using the 2.4 GHz band and AirPlay on this iPod touch to play music on the Denon receiver. Again, I was able to establish a connection and successfully play music, but after a few minutes the connection dropped and the music stopped playing. I therefore have concluded that I have a poor wireless connection in the master bedroom. I can establish a connection, but it is intermittent with frequent drops. I have verified this with both laptops by working in the master bedroom for an entire day on both laptops. The Internet connection in this master bedroom proved to drop out frequently - about once an hour with the laptops. The wireless connection and the frequency of its dropout are far worse with the iPod touch and an iPhone.
I cannot relocate the TC. Also, this is an apartment and I therefore cannot extend the range of my network with Ethernet cable (I cannot drill through walls/ceilings, etc.). It is an old building with antiquated wiring and power-line adapters are not likely to function properly, nor can I spare the direct power outlet required with a power-line adapter. I simply need every outlet I can get and cannot afford to block any direct outlet.
My solution is to use a more powerful wireless router. I found the ASUS RT-AC66U Dual-Band Wireless-AC1750 Gigabit Router which will likely provide a better connection to my wireless Internet in the master bedroom than the TC. The 802.11ac band of this Asus wireless router is totally useless to me, but based on what I have read I believe this router will provide a stronger connection at greater distances then my TC. And I will be ready for 802.11ac when it becomes more widely available.
However, I still need to maintain the TC's ability to work seamlessly with TM to backup my two laptops. Also, I doubt the new Asus router will provide OS X 10.8.2 with NAS like features and capabilities. Therefore, I still would like to use the TC's NAS capabilities to share files on my network wirelessly assuming the Asus wireless router fails to provide this feature. I need a new and more powerful wireless router, but I need to maintain the TC's NAS features and seamless integration with TM. Finally, I want to continue to use my Apple laptop and AirPlay to wirelessly access and play my iTunes music collection stored on the TC's hard drive. I also want to continue to use my Apple laptop, AirPlay and Apple TV to wirelessly watch movies and TV shows stored on the additional external hard drive connected to the TC via USB. Can someone advise on how to set-up my existing TC with this new Asus wireless router in such a way to accomplish all of this?
Modem
Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem
Existing Wireless Router and Primary Wi-Fi Base Station - Apple Time Capsule
Apple Time Capsule MC343LL/A 1TB Sim DualBand (purchased June 2010, likely the Winter 2009 Model)
Desired New Wireless Router and Primary Wi-Fi Base Station - Non-Apple Asus
ASUS RT-AC66U Dual-Band Wireless-AC1750 Gigabit Router
Extended Wi-Fi Base Station - Provides an Ethernet Connection to a Denon A/V Receiver Two Rooms Away from the Modem
Netgear Universal Dual Band Wireless Internet Adapter for TV & Blu-Ray (WNCE3001)
Addition External Hard Drive Attached to the Existing Apple Time Capsule via USB
WD My Book Studio 4TB Mac External Hard Drive Storage USB 3.0
Existing Laptops on the Wireless Network Requiring Time Machine Backups
MacBook Air (11-inch, Mid 2012) OS X 10.8.2
MacBook Pro (13-inch Mid 2010) OS X 10.8.2
Other Existing Apple Products (Clients) on the Wireless Network
iPod Touch (second generation) is model A1288.
iPad (1st generation)
Apple TV (3rd generation) - Quantity two (2)

Answer 1

Thanks Bob Timmons.
In regards to a Plan B, I hear ya brother. I am already on what feels like Plan Z. Getting WiFi to a far off room in an apartment building crowded with WiFi routers is a major pain.
I am basing my thoughts on the potential of a new and more powerful router reaching the far off master bedroom based on positive reviews on cnet.com, pcmag.com and pcworld.com. All 3 of these web sites have reviewed the Asus RT-AC66U 802.11AC wireless router as well as its virtual twin cousin 802.11n router. What impressed me is that all 3 sites rated this router #1 overall in terms of both range and speed (in both the 802.11n and 802.11AC flavors). They tested the router in real world scenarios where the router needed to compete with a lot of other wireless routers. One of the sites even buried this Asus router in a media room with thick walls and inside a media cabinet. This Asus router should be able to serve my 2.4 GHz band wireless clients (iPod Touch and iPhone 4) with a 2.4GHz Wireless-N band offering some 50 feet of dependable range and a 60 Mbps throughput at that range. I am hoping that works, but it's borderline for my master bedroom. My 5 GHz wireless clients (laptops) will enjoy a 5GHz Wireless-N band offering 150 feet of range and a 200 Mbps throughput at that range. I have no idea what most of that stuff means, but I did also read that Asus could reach 300 feet and I got really excited. My mileage may vary of course and I'm sure I'm making some mistakes in my interpretation of their data. However, my Winter 2009 Time Capsule was rated by cnet.com to deliver real world performance of less than that, and 802.11AC may or may not be useful to me someday. But when this Asus arrives and provides anything other than an excellent and consistent wireless signal without drops in the master bedroom it's going right back!
Your solution sounds great, but I have some questions. I'm using OS X 10.8.2 and Airport Utility (version 6.1 610.31) and on its third tab labeled "Wireless" the top option enables you to set "Network Mode" to either:
Create a wireless network
Extend a wireless network
Off
Given your advice to "Turn off the wireless on the TC," should I set Network Mode to Off? Sorry, I'm clueless in regards to how to turn off the wireless on the TC any other way. Can you provide specific steps on how to turn off the wireless on the TC? If what I wrote is correct then what should the rest of this Wireless tab look like, or perhaps it is irrelevant when wireless is off?
Next, what do you mean by "Configure the TC in Bridge Mode?" Under Airports Utility's fourth tab labeled "Network" the top option "Router Mode" allows for either:
DHCP and Nat
DHCP Only
Off (Bridge Mode)
Is your advice to Configure the TC in Bridge Mode as simple as setting Router Mode to Off (Bridge Mode)? If yes, then what should the rest of this "Network" tab look like? Anything else involved in configuring the TC in Bridge Mode or is it really as simple as setting the Router Mode to "Off (Bridge Mode)"?
How about the other tabs in Airport Utility, can they all stay as is assuming I use the same network name and password for the new Asus wireless router? Or do I need to make any other changes to the TC via Airport Utility?
Finally, in regards to your Plan B suggestion. I agree. But do you have a Plan B for me? I would greatly appreciate any alternative you could provide. Specifically, if you needed a TC's Internet connection to reach a far off corner of your home how would you do it? In the master bedroom I need both a wired Ethernet connection for the Denon a/v receiver and wireless Internet connection for the iPhone and iPod Touch.
Power-Line Adapters - High Cost, Blocks at Least One Wall Outlet and Does Not Solve the Wireless Need
I actually like exactly one power-line adapter, which is the D-Link DHP-540 PowerLine AV 500 4-Port Gigabit Switch. This D-Link power-line adapter plugs into your wall outlet with a normal sized plug (regular standard power cord much like any other electronic device) instead of all of the other recommended power-line adapters that not only use at least one wall outlet but also often block the second outlet. You cannot use a power strip with a power-line adapter which is very impractical for me. And everything about my home is strange and upside down. The wiring here is a disaster and I don't have faith in its ability to carry Internet access from the living room to the master bedroom. And this D-Link power-line adapter costs $90 each and I need at least two to make the connection to the Denon A/V receiver. So, $180 on this solution and I still don't have a dependable drop free wireless connection in the master bedroom. The Denon might get its Ethernet Internet connection from the power-line adapter, but if I want to use an iPhone 4 or iPod Touch to stream AirPlay music to the Denon wirelessly (Pandora/iTunes, etc.) from the master bedroom the wireless connection will not be stable in there and I've already spent $190 on just the two power-line adapters needed.
Extenders / Repeaters / Wirelessly Extending the Wireless Network
I have also read great things about the Amped Wireless High Power Wireless-N 600mW Gigabit Dual Band Range Extender (Repeater) SR20000G and the My Net Wi-Fi Range Extender. The former is very powerful and the latter is easier to install. Both cost about $150 ish so similar to a new Asus router. However, everything I read about Range Extenders points to them not being very effective for a far off corner of your house wherein it's apparently hard to place the range extender in the sweet spot where it both gets a strong enough signal to actually effectively extend the wireless signal and otherwise does not reduce network throughput speeds to unacceptable speeds.
Creating a Roaming Network By Hard Wiring with Ethernet Cable - Wife Would Say, "**** No!"
Even Apple seems to warn against wirelessly extending your network (see: http://support.apple.com/kb/HT4145#) and otherwise strongly recommends a roaming network where Ethernet cable is used to connect two wireless base stations. However, I am in an apartment where stringing together two wireless base stations with Ethernet cable would have an extremely low wife acceptance factor (WAF). I cannot (both contractually and from a skill prospective) hide Ethernet wire in the walls or ceiling. And having visible Ethernet cable running from room-to-room would be unacceptable, especially to the wife.
So what is left? Do you have a Plan B for me? Thanks in advance for your help!