Why can't i post my question

Question

why can't i post my question

Answer 1

The 2nd ethernet connection goes to an ethernet splitter that connects to my Yamaha Amp, Apple TV Living Room, thunderbolt connected MacBook Air, Bell HD PVR Sat Receiver and Xbox One. 
By splitter I presume you mean switch.. as long as it is gigabit there is no issues.
Some of you info is a bit hard to follow and I cannot really comment.. wireless links are necessary evil but to be avoided as much as possible.. in particular no double hop wireless.. that means all wireless AP should be ethernet linked back to a main router.. when you extend wireless you halve the speed. You also make the network less reliable.
I have used the "Guest Network" in an attempt to prioritize specific home connections when Guests arrive.
Guests is for keeping the clients out of the main network.. it has no particular QoS attached to it.. although when you extend wireless in guest network it does seem to go super slow.. this I think is more a bug than deliberate. Apple routers have no support for qos.
What is the best configuration?
All ethernet.. any wireless should not be extended.. only single hop to any wireless access point.
Should I attempt to assign wireless channels to our devices to improve connections?
Only if auto fails.. if it does then take control of the whole thing.. but you need to spend some time doing wireless surveys around the house.. start with the main AE with nothing else.. work out what signal levels you get and where the dark areas are.. then power on the TC and whatever express are associated and do the survey again.. get levels of each AP as seen by client in the places you want to use them.. conflicting wireless signals should be separated as much as possible but it is not so easy as there are only 3 non-overlapping channels at 2.4ghz namely 1, 6, 11 and using in between channels is not really going to help. 5ghz has more available channels but AC chews up 80mhz by itself so that doesn't leave so many.. although 5ghz wireless range is less so interference is less of an issue.
You also have to check what wireless is around you.. and that adds so much to complexity you might as well leave things on auto.. although I break that rule when I extend wireless because I think it is less than stable so the less auto the better.. and another reason to avoid extend wireless.
Or assign static IP addressees to the ethernet wired components?
Static IP can help but you should always use dhcp reservation on the main router. That helps to keep the ARP tables correct.. although Yosemite has real network issues.