Aarons. I fell into the same trap as you with the going MYTH that separates will give you better sound. That may have been true 30 years ago when the vast majority of receivers were crap and used high voltage no current to get impressive numbers on paper but could not drive a speaker.

I spent too much money trying to get better sound with big box store components that never worked. I ended up like Nickbuol and bought an Anthem pre-amp as I owned external amps already. Can't say why but the sound quality was night and day better.

You can buy the MRX-720 if you don't need the atmos right away and save some coin. They have some of the best room correction out there,

But reality is, a better designed room will give you better sound. That is where i would start looking.

Anthem: AVM60
Axiom: ADA1000, LFR1100, VP180, QS8, EP500, M3, M3comp
AudioSource: Amp One/A