It has been a long time since I last played Minecraft (or at least the IC2 part of it, I'm a big fan of technical minecraft), so I might not remember things correctly. Anyway, I'll try my best to answer your questions.
1. Depending on your needs. You can put the access hatch, redstone port, fluid ports wherever you like as long as you can get all the (hot) coolant in/out.
a) If you just put 1 ejector upgrade inside a single port, 15 is needed.
b) This is highly flexible. You can use the heat to generate biogas, steam, superheated steam, or directly into EU via the stirling generator. There might be more options that I can't remember but more info is available on the wiki and here. Each one has its own pros and cons, which is up to you to decide.
1) What else would I need in order to use superheated steam for power?
a) what upgrades would each thing need?
2) What would the layout need to look like?
a) Is it possible to have everything off to one side of the reactor?
b) Is it possible to set up superheated steam with this setup?
c) If the layout above is not feasible, then is this layout below feasible?
Ideally, I would like to have everything branch off the reactor on only one side. Thank you