there are definitely smaller and simpler ways to synchronize if that is the main motivation for Hermod, but if you want the sequencing it provides, that’s another story. since you already have a Digitakt/OP-1/OP-Z, all of which can sequence in various ways, I’d personally be inclined to replace Hermod with something to provide sync (Yarns, FH-1, µMIDI for example) and add maybe something like a Maths or other versatile, immediate modulation source…unless you want this to be more self sufficient/able to be used without the other sequencers.
in either case, I’d also want some kind of VCA (many options)/lowpass gate (DPLPG, Optomix, LxD, etc) type modules to control voices/modulations. Cold Mac can do that, but you’ll probably have many other uses for it beyond basic VCA duties.