Multi channel Amps for a 7.2 setup based on PSB Synchrony 1 series + SVS Subs

Hi, 
I am lucky enough to have recently moved into a home where I can setup a dedicated HT/Music/rec room, and am today seeking your advice/guidance on how to properly setup this room, select equipment on a budget, and generally turn a bare 21X15X9' room into a modest powerhouse!

I recently jumped on the opportunity to acquire a mint pair of PSB Synchrony 1 Towers, and went on from there to secure a pair of Synchrony 1B bookshelves and two pairs of Synchrony S surrounds. The low end will be boosted by a pair of SVS SB2000 Pro Subs. So it looks like I'm OK where it concerns speakers.

For the moment, I will have to settle for a DENON AVR 4310 Ci to drive the speakers, although I am seriously contemplating the acquisition of a three channel amplifier to drive the front three with the necessary juice.

Questions:
- What three channel amp will be a good match with the PSB front three?
- For the moment, the DENON will drive the rear and surround speakers... Is this OK? 
- I realize that the next step will be to replace the DENON with a better processor, and whereas this will come at a later stage, I welcome your advice and recommendations as to what equipment would make a discernable difference in SQ, etc. 
-  How desirable is ATMOS at this point? My previous even more modest setup was a 5.1 system which I really enjoyed quite a bit. I'm thus not in a hurry to add all these new technologies if that will help keep the hobby's budget reasonable... Is this a mistake on my part? Am I missing something by not adopting these new technologies? 

I'm thinking that before I splurge hard earned funds on Atmos, etc. I'd rather spend it on room treatments, a better projection screen and projector. Am I approaching things the right way?

Voilà! Lastly, while this will be a HT focused system, 2 channel music listening is also part of the equation (70-30% should be the proportions. I really want to enjoy the Synchrony 1 Towers as they are touted as being lifetime speakers material. Stereophile A list speakers for years if I'm not mistaken.

Apologies for the long message, and thanks in advance for sharing your experiences, advice, guidance, pointers, etc.
Regards to all, jlr261