Imho you can't overpower a room, I've owned the 60's and now own the 80's, for your room size the 60's would be more than enough, they are really great speakers. But if you can afford it and want to avoid upgradeitis go with Axioms best, you can always turn them down
If you want to save some cash go with the QS4's and a VP100 along with M60's and I think you would be more than happy. As far as the sub goes stay with the EP500 because you will never regret that choice, it's that good!

A computer once beat me at chess, but it was no match for me at kick boxing.