I also have a dedicated HT / listening room about those dimensions and run 7 channels all Magnepan. I painted the screen wall & ceiling all black and the rest a darker grey. It really helps to make the screen pop.
I run the screen + 1.7's, CC5 and subwoofers across the front short wall. I have Ikea Expedit bookshelves that run about 3/4 of each long wall to serve as diffraction and also storage for books & media. This does remove another foot from each side, so speakers + a 96' Stewart Studiotek 130 screen just barely fit along the short wall. It's a 16:9, and that's what I would suggest as most HD media is in that size and you don't have to worry / mess w/ masking.
With what space is available the speakers are probably closer to the back and side (less important) walls than ideal. The first row (two recliners) is about 8-10 feet away, and also have a second row along the back wall which is raised about 8 inches on a platform so they can see over the first row.
Guess the message is to measure very carefully before committing yourself to larger speakers / screens - there's less room to work with than you might imagine.
A few other random comments :
1) The room length gave me two bass nodes, but using a three foot bass trap wedge from ATS (I think) in each front corner seemed to take care of that. The bass traps are not that expensive & available in a range of colors & fabrics. They are heavy so shipping is a bit pricey.
2) I tried both the MMG-C and CC5 center channels & didn't feel the CC5 was 4 times better at 4 times the cost. It was more efficient and played louder and was somewhat better of a timbre match for the 1.7's as it's QR. So would caution against spending the even bigger bucks for the CCR unless you can try before you buy.
3) I use regular full size MMG's on custom (door) hinges for the surround L/R and MMG-W's for the rear two channels. I think the MMG's are probably overkill, and 1.7's would be even greater overkill. There seem to be very little source material that makes abundant use of the surrounds, particularly at the lower frequencies. The front two channels, then the center channel really make the biggest difference. So i'd say save the $ and use MMG-W's for surround sound duty.
4) You'll really want one or more subwoofers for the home theater use. They don't have to be super high-end : I use two entry level Velodynes I bought used for next to nothing. If you do want to go high end, BG-Radia's in wall subwoofer panels are some of the most impressive I've heard. But even a single good subwoofer from SVS or HSU would do the trick in a room that size.
5) All the lights from all the gear on the rack can get a bit distracting in a darkened room, but on the other hand, if it's not line-of-sight you'll have problems with the remotes. So have the rack preferably have a nice tinted glass door, or invest in an IR repeater so you can have the gear out of view if you prefer.
Best of luck & enjoy!
