It’s all about context isn’t it?
For low mix, killed low freqs, density reverb over my OT’s main output (pre Heat), I use Eventide Blackhole.
Space would also suit here.
Though I would eventually like to, instead, use a Source Audio Ventris.
Ventris’ parallel dual stereo reverb, running plate on one processor (so good on drums) and another density based algorithm on the other (modverb?)… could be even better, and frees up OT FX slots as you want hear any dark verb behind heavily eq’d reverb on a master output at a low mix setting. So FX slots can be used for EQ and compression, the stuff that makes a mix pop.
For synths I’m all ears for any pedal that can do what NI’s Raum does.
Euro wise… Audio Damage’s discontinued AEVerb is based on EOS, which uses a Valhalla algorithms. Usable on just about anything .
Some good recommendations here as well: