I agree that speakers are more important than the rest. Equally important is how the room responds to the speakers. And using two subs is also recomended because it evens out the room mode related anomalies.
So, yes, by all means, if possible try to invest in room treatments: put 4" thick absorbers against the first reflection points and check out bass absorbers.
Then Room Correction comes into play. Probably the best of the user friendly (automated) room corrections today is Audyssey MultEQ XT32. XT32 is 32 times more resolution for the mains and 4 times more for subs than XT. XT32 needs more processing power hence is in more expensive AVR's. There's also even more basic MultEQ and 2EQ.
The cheapest AVR with XT32 is the Onkyo TX-NR818 (MSRP 1,200 USD). Denon only offers XT-32 in the AVR-4520CI, which is $2,500 (also as an upgrade in the AVP etc, but that is more $). If you want Denon there are the AVR-3313CI ($1,200) and 2313 ($900), both with XT. The 3313 has a few more watts, but for the rest there isn't much in them (compare them on the website to see if there's something you need). The price difference pays for half the XPA-3...
And I can confirm that Yamaha is very reliable since my RX-V2700 has never missed a beat since 2007 although it's always on if somebody is at home. My son plays his PS3 through it, we watch TV or Blu-ray and it's zone plays music in my office. But the successor RX-A3020 now costs $2,200. The RX-A820 maybe all you need at $900. The YPAO room correction in it uses 8 in-room positions ("multipoint) like XT, but it doesn't say much about how it treats the subs.
All prices MSRP.