I don't know how much you've built but here's some advice on the building process first
1) Leave yourself open for one or two passive subwoofers at the back of the room, with 12 awg wire for higher power handling.

2) Leave yourself open for rear surrounds as well (7.x) "just in case". 14 awg wire is fine.
3) Build an isolated, but ventilated electronics rack for placing amps etc in the future.
4) Install a dedicated 20a circuit or two instead of the usual 15a circuit.
5) Build your walls to flex and absorb bass. Perhaps read this:
http://www.earsc.com/pdfs/engineering/understandingdamping.pdf
Especially the part about constrained layer damping (CLD)
6) Make a conduit for a projector "just in case"
Besides all that, i'm glad you decided against Bose. That stuff's just bad for your health.
Can I get a rough budget, if possible, as well as some information on your seating position in the room?