Then I’d certainly recommend that you not use a soundbar. Due to the physics of locating all speakers in a single enclosure, there will always be limitations to how “good” any sound bar sounds. You’d be much better off with a full dedicated 24.1.10 system, with the necessary speakers and amplifier to run them. 

I understand the limitations of a soundbar vs separate AV Amp and speakers. I am comparing what I am hearing now with (Atmos via DD+) on the Arc+Sub vs what I was hearing before with Playbar+Sub (DD), which appears to be a limitation of HDMI-ARC from what I have read above.

I’d certainly expect a difference between 10 channels, and 24 channels, beyond the simple physics of a sound bar. I’d be terribly surprised if you could hear a difference between the two on a soundbar, but I’ve not tested, and could be wrong. It’s one of the reasons I’m so interested in the opportunity to get an eARC signal to my Arc, using the device discussed here.  I’m interested in maximizing the signal I can get out of the device I was willing to drop $800 on, but not compare it to a system that I would need to drop many thousands on. 

I do love Sonos for the setups I have in both my living room and bedroom. But I recognize they’re not the end all of sound setups.