Warm Star Electronics has a module called The Bends in 10hp. That might be an option to look for. You can find them used occasionally and they are fairly inexpensive.
-- farkas

Wow, this looks fantastic and extremely well thought out! Thank you for the tip, I hope I'll find one on the secondary market since they don't ship outside of the US...

alternative: doepfer matrix mixer
-- JimHowell1970

Definitely on the shortlist, although the knob matrix is almost a bit crammed imo. Thank you for the suggestion!