Thanks for all of the really useful advice. I will keep in mind the 'one module for one purpose' rule!

Perhaps a Doepfer A-138s as a stereo input for soft synths? They are a good price at the moment.

EDIT: actually, it appears that I'd need an Expert Sleepers module. Is that correct? I can send cv from my Presonus Q2626, but it seems that I'd need as ES module to receive it?

This is getting confusing...