dave, your understanding of the holy trinity (vibrations, AC & room) is impressive; if i had to boil down how to build a good sounding rig, you nailed it.
appreciate your thoughts on vibration control. FWIW, i got great results with AC by using the wall plates and dedicated vibration control of AC distribution boxes (critical!), and the addition of a technical ground as described on equitech's website took my resolution over the top. YMMV, but thought you'd appreciate these findings.
best