Not particularly in my experience. I had an old 2ch receiver back in the day (70s) and moved up to separates (i.e. separate tuner/pre-amp/amp boxes) and while I tripled my power, no other significant difference in SQ nor when I moved on from that setup to my current batch of avrs (and I still use some of that old 2ch gear). The changes were when I moved speakers to different rooms/houses, and the speakers themselves. There's a lot of generally baseless chatter on the net from 2ch gearheads on the subject IMO, though
![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Some of those guys hear differences in cables, too.
As was pointed out, perhaps looking at your room/setup now in detail would be the best first step, to maximize what you've got. You've got good stuff....