Understanding AP Network Speed

Question

Just typed up a long and thorough description of the configuration and performance of my AirPort network, which the forum software proceeded to throw away (except for the title) when I navigated away to edit my product list. Lovely.
Nutshell...
My FiOS Quantum 75/35 service is giving me about 80Mbps straight out of the Ethernet port, as measured via Speedtest.net.
By and large, my 2008 model MBP is getting me around a quarter of that when connected wirelessly via the 5Ghz network, more or less regardless of where I go around the house.
My iOS devices are giving me about a third to a quarter of what the laptop is providing–six to eight percent of at-the-port throughput, in othe words—with the iPad 2 on the 5Ghz network, and the iPhone 4S on the 2.4 (it can't ever seem to find the five).
It's a fairly big, fairly brick-y house, 170 years old. Stringing Ethernet throughout is not an option, as much as I'd love to. In addition to the dual-channel base station, my network has three Airport Express 802.11n's, all set up to "Extend a wireless network."
I know that my house is not nirvana for wireless, and that I'm not going to get test bench throughput from my Airport devices in any event. But a factor of 15 degradation with my iOS devices seems kinda severe. I can live with factor of four with the laptop, I guess, but even that seems like kinda lousy performance.
Thoughts? Ideas? Pointers? Any and all would be appreciated.

Answer 1

So, a couple of things.
First, in preparing to test out a powerline network, I took down all of my AirPort Express units. Before doing anything further, my throughput went up by factors of two or more in most locations around the house. Since AirPlay, Bluetooth, and Apple TV can handle all our media streaming needs, I will no longer be using the APEs. So, addition—really, multiplication—by subtraction. Progress!
I've been utterly frustrated, however, in trying to establish the powerline network. I bought two D-Link 500MBps adapters. Plugged oneinto the wall by my router, then plugged my AirPort Extreme base station into it. Plugged the other into the wall in my dining room, where I wanted to test its performance. Went through the configuration per the manual, and followed Apple's steps for setting up a roaming network. No freakin' joy; I can't get a valid IP address out of the "remote" adapter (Yes,  I confirmed that the base station was sending a non-bogus one to the "base" adapter).
Called D-Link tech support. Turns out, the "only problem" with the product is that they won't work unless they're plugged into the same electrical circuit.
Gosh, was that the "only problem" with the play, Mrs Lincoln? I mean, my house is over 3,000 sq ft and must have 15 separate circuits; what decent-size house doesn't? What are the odds that two arbitrary rooms will share the same breaker? Not great, at least in my 19th century Victorian.
I had read that there could be difficulty if the units were plugged into different power *phases* (120 vs 240). I checked my breaker box, and all seems to be right on that score; both circuits appear to be on the 120 phase, flowing from the main power distribution panel.
What really frosted my nads was that the adapter features an LED that is alleged to indicate that the device is connected to the network and communicating with its comrade(s). Turns out, not so much. Even though both of mine are shining a lovely, steady green—indicating not just that they are in contact, but are communicating at 80+ MBps—they're really not connected at all. In fact, according to D-Link tech support, all the "PowerLine Network LED" is telling me is that the unit is receiving power. Which I thought was the job of the cleverly-named "Power LED." Silly me.
Are there any powerline products out there that don't suffer from this insignificant, tennsy-weensy, little flaw?