Gosh darn. Had to buy Virtual Soundstage 2, despite all the reasons not to -- I just can't get the same kinds of results with anything else I've tried! It's kind of pricey for what it is, so I bought the single-room edition, as that room was the only one I really liked, anyway.
MVerb is great but it doesn't have an integrated multi-track UI to easily manage everything for like, a whole orchestra. eaReverb has one, but it's not as easy to use with a lot of different tracks (at least not on the demo, it only lets you edit the specific track you've opened the plugin for, unlike VSS2 where it doesn't really matter which instance you click because it's all synced to one main instance in all reality.
VSS2 is as far as I can tell, still the only dedicated ERs-only generator out there.
I can also confirm the eaReverb does work on macOS 12 (I'm running an M1) -- it's just not officially supported, or the demo works, at least.