If you like how the Klipsh sounds that is all that matters really. Don't listen to the negatives about Klipsh you like them and thats what counts. I like your choices except the sub. You should check out
www.svsound.com or
www.hsuresearch.com as the Klipsh subs are nowhere near as good as either of those.
I couldn't agree more. Besides, Klipsch speakers are pretty damn good(IMHO). Hell, there is a reason(a good one at that)that they have been around as lond as they have.
One thing though. I would also have to agree with the subwoofer choice you made, not being the best(IMO). I know I have an Aperion Audio Subwoofer,(and I love it for now)but my next move up will be an SVS sub(looking at the PB 13 Ultra)
You may want to look into some of the newer AVRs out there. Yamaha, Denon, and Onkyo

D), all have great offereings in the Home Theater Receiver range.
As far as your room's acoustics are concerned, that half wall will definitely pose sound issues. Maybe even an acoustic type of curtain of some sort, hanging from the ceiling to the flloor and directly up against that half wall. I am guessing that something like that would make a very noticeable difference in the sound(positive difference), though it may be an unsightly difference too though. That, along with bass traps and some accoustic treatments, should really make for some great improvements in your overall sound experience.
I am sure you will get plenty of imput here. There are many members here with much more knowledge than I have.
I wish you the best of luck on your new project. It's sure to be a whole lot of fun!!

Joe B.