Pic #4: rack gear installed. It's still only about 1/2 wired, but this gets me 2 mic inputs and 2.1 monitoring (sitting on the countertop

)
It still needs filling, finished, and a glass door salvaged from an old home stereo tower case cut to size and installed. I'll try to get the glass door in this week
Stage 2, I'm gonna build a few framed wall-mount absorbers, and stuff some 4" rigid fiberglass over the bookshelves for some temporary treatment.
Stage 3 construction involves tearing the drywall off the ceiling & walls, installing mic cable in the walls, mounting newly built monitors in the walls, rebuilding soundproof walls & ceiling, building a floating cloud, and adding 5.1 surround

A little bit harder, I think