The Stillson Hammer mkII can definitely function effectively as a master clock. It even has a direct clock out with no division/multiplication as a normalized patchpoint. Given that, you could easily run a trigger sequencer such as a Four Bricks Rook, Circadian Rhythms, Knit Rider, etc from that to provide various rhythm patterns in sync to pass on to the MS-20, Juno, etc, plus most any sort of clock modulation module will work nicely for clock maths.