Welcome, FearFX,
Before I do my best on your questions, something you might consider is that by the time you add stands for the M22s (much mo' betta than placing them on shelves or in entertainment centers), they will take up almost as much room as the M60s, though not seem as massive.
1. VP150 would NOT be overkill, and yes, it would match the M22s just fine.
2. Yes, The QS8s are very forgiving when it comes to placement. From the Axiom FAQ:
Ideally, surround speakers should be either wall-mounted or stand-mounted to either side of the couch or primary listening area, from one to six feet higher than seated listeners' ears, and slightly forward or rearwards of the listening area if you wish. Axiom's Quadpolar surrounds are especially versatile and can yield excellent performance with stand or wall-mounting to the rear as well as at side locations. (see our dedicated stands for the QS Surround speakers in the Store). Rear center speakers for 6.1 and 7.1 installations are intended to go on the rear wall at about the same height as the surround speakers..
3. Either the side wall or the back will work. If you can, experiment to see which placement you prefer.
4. I'm no help on this one. I've never heard the Deftechs.
