One more thing, another interesting data point. We all know that for best speaker performance, they should be some distance out from any wall.

I can do this easily for the 3 fronts, but 3 of the 4 surrounds and rears are within 6" of a wall. I do the trick of crossing them over at 100 Hz, (even though their -3 dB pt is 45 Hz), just to try to limit the "boxy" and "bloated" bass that's possible.