It's a fascinating quest any way you pursue it. In my own career I've enjoyed the experience of creating many 'great rooms' with an emphasis on acoustics as well as aesthetics. A couple of the things I seem to have learned fly somewhat in the face of accepted practice as well as scientific logic (well, almost). Asymmetry is prime among these, so I was pleased to see your remarks along those lines.
Three things do stand out as universal IME: First, extended ceiling heights. Ten, twelve, fifteen feet high if you can manage it, maintained within proportion to the room's other dimensions of course. Complex, sloping planes can work very well, but need to be managed expertly. Secondly, avoid large, unbroken, continuous surfaces of any kind. Third, wood is an attractive and popular material but it's best if it's open-pore and unvarnished. I've seen a lot of wood finished with gloss polyurethane and it's nearly as reflective as glass.
I definitely agree that the room is the single most important element in the quality of your music listening.