Any of the processors you mention should have better sound than the 8 year old Denon. Anthem designs are always a little behind the curve but speaking from experience the Anthem Room Correction (ARC) is easy to set up and tweak. The software gets the sound to 90%, fine tuning by ear is always required to get the best home theater experience. I think the Anthem sound is excellent, it is never harsh or peaky at high levels and at the other end, the quiet whispers in Dune: Part 1 were clear and easy to understand.
What speakers do you have? The processors you are looking at are all state-of-the art. I have matching Salk speakers for the front and Triad for the surround and Atmos speakers, theater level loudness is not a problem, I usually turn it down. My room isn't as problematic as yours.
If you want Dirac ART you should get it.