Wow where to begin
I think everyone here will agree that upgrading to a speaker system with a better sound stage will blow you away, compared to BOSE cubes, especially in that huge room. It sounds like the system will be used primarily for movies and less for music listening? Also, a lot depends on your budget?
Are you still planning on using the projection tv. I would highly consider looking at Front Projection as you could get a real movie experience with a much larger image on that back wall. I have 120" diag., nothing like haveing a movie theater in your own home if you can swing it....especially when you in the process of building the home. I would plan for 7.1 for the future, although, you can start with 5.1 and move up when you want.
Normal rule of thumb is you want to be 1.5 times the screen width back. That is for projector screens, not sure about smaller projection tv's. Also, you want your eye level to be 1/3 from the bottom of the screen, again, that is for projector screens.
good luck
Randy
m60's vp150 ep350 4-qs8's
denon 2805
sanyo Z2 WXGA projector
toshiba dvd
samsung hd tuner
