Moral of the story = moving sucks.
I can't comment on a lot of this, but you could try buying a pair of Fluance XLBP to use as your surrounds. Maybe the more diffuse output of bipoles will help with your multiple row seating.
Wiring them, bury the wire in the seam between the wall shoe molding and the carpet. Make liberal use of wiremold (or similar cable management conduit) to run from seam to speaker.
So your HT room is 9' x 18'? I sit about 15 feet from my 67" display and it looks just right to me.
That sounds like kind of a small-ish room to be shoehorning two rows of seating to me. You might have to choose between the front row being too close to a large display, the back row being too far away from a small display, or fewer seats. I'm having a hard time envisioning how things will fit into the room, though. Maybe you could download Google Sketchup and hack up a model of what to expect.
Since you're limited on space, you might consider building a pair of small sonosubs to save on real estate.
I just modeled one with an 8" RE Audio driver you might find interesting. Not sure whether it'll play as loud you like to listen, but it'll definitely play deep for such a small footprint. (For what it's worth, I think it'll at least be stronger than an SVS SB2000 below 30Hz).
For speakers to use on the sides of a flat panel, look for front ported. The WaveCrest HVL-1 would be a good example. Move the DefTechs to the family room.
That's as much concentration as I can spare for the moment. I just saw something shiny.