Its has been said many times that the M80's are easily driven by any of the reputable AVR's, Denon Onkyo Yamaha etc. I take it you like it a little loud as you say the RV1200 is a little under powered, if this is correct I would suggest using seperates as the slight increase in power output above the RXV1200 is negligble. You may want to try the HT wizard here or give Axiom a call just to see what they suggest as well.
I do feel that the M60's would do the job but the 80s are said to play louder which is why I went with them first. As for QS8's, I feel they are the best surround you can get, no problems there.
Good Luck
