I'm following your current 'add sub(s) to these' discussion.
I might try adding hanging a blanket over the front of the TV and Fireplace, perhaps a broomstick, staple a quilt onto it, roll it up, simply unroll it partially or fully, and put the broomstick behind the top of the TV when listening. I do something like that when I need a photo backdrop shooting clothes Donna sells on eBay, I hang white cloth over a large painting. On/off, easy.
Video: center speaker and rear l/r in the future, or just darn good 2 channel sound for video? I often force 2 Channel Stereo and prefer it. Surround is awesome for Jurassic Park, Black Hawk Down, ....I prefer the center to come from just below the image. TV's need to be built to use their built-in speakers just for center.