Not exactly but sort of.. I am recommending those amps now because:
- Not familiar with GR Research line arrays but googling it found the LS9 that are huge and can take up to 500 watts. Since you did say "Those two speakers can basically handle anything, I'm always amazed with them." so I made my assumption that's the model you have. Since those speakers are huge, I therefore assume you would sit at least 12 ft or further away from the speakers (you just confirmed that part).
- You also said: "I have in the past strayed away from AVR's because they didn't sound as good to me, that was 7-10 years ago." So right or wrong, factual or Placebo, you have preconception about the "AVR sound".
For processor though, I am quite confident with the X4500H because I have the X4400H that sounds as good as my separates, not just the former Marantz AVP but also my real preamp/power amps. It for sure has high and clean enough pre out to drive any 200-500 WPC power amps. If saving money is not your priority though, the CX-A5200 that
@AcuDefTechGuy recommended is an excellent value. By the way, in my opinion you don't need to spend money on expensive power amps for the surround speakers, but the center speaker is a demanding on so you shouldn't short change it.