Great thread and theater design, Ronnie. I finally got around to checking yours out and am hooked, of course.
I'm glad you went with the combination of curved and curtains. The extra wide L & R speaker walls looked a bit large in your first rendering. You also have the ability to convert to 2.35:1 constant height, as many are doing lately it seems. All you'll have to do is move the curtains to the side.
I like your columns as well - I agree with others who've said that the wooden sides would maybe be a bit wider, and my additional thought on the subject is to possibly push them in a hair, so they don't stick out much more than the black fabric (approx 3/4" perhaps).
The last render you posted does indeed look odd to me, too. Centered on the side wall soffit that it's on may look a bit more symmetrical. It seems that Bryan has nudged you in that direction and you've agreed, so that should look great as well.
As far as the side surround speakers influencing the column location, I've thrown around the idea of putting two side surrounds on each side (essentially 9 channels including the rears), which should help diffuse the sound from the sides even more. The only additional requirement (other than two more speakers) would be an amplifier to power those additional channels. Obviously you'd cut the gain approximately in half at that point. I would imagine it would sound a bit better no matter which row you're in. I'm not sure if anyone else on AVS has done this (I'm sure someone has) or their results. If your column placement now favors a single side surround then obviously it's moot.
Awesome job.. the proscenium especially is a motivating factor.. Just don't hook up a projector!