I wasn't able to get to your pictures (got a 404 error - it looks like the links got a bit truncated), but when we moved into our current house about a year and a half ago I found that the walls that needed to carry the side surrounds simply would not accommodate my Studio/ADP surrounds. I had initially planned to leave the ADP's as side surrounds and get a pair of smallish bookshelf speakers for rear surrounds (previously I'd used a single ADP for a 6.1 arrangement), but due to the fireplace and french doors I was forced to scrap that idea and move the ADP's to rear surround (where they seem to have worked out quite well, actually) and replace them at side surround with a pair of Axiom M3ti bookshelf speakers on adjustable wall brackets. I even had to connect one speaker's bracket to the side of the speaker to avoid the brick surround on the fireplace. I never had towers for surround detail, but I've had good luck with both dipole and direct radiating bookshelf speakers - remember, the 990 will let you cross over bass to the sub so they don't have to reach real low.

Here are some pictures of my setup: right side and rear surrounds , rear surrounds and left side surround (left side surround is hiding in shadows to the left of the fireplace), and left side surround .