I recently participated in a drum circle and recorded part of it. As an experiment, I wanted to see if I could sync a synthetic rhythm in VCV Rack with the organic rhythms in the original recording. I tried several ways of using envelope followers, etc, but nothing worked as well as I wanted.
I ended up using Audacity to find the time offset of each beat and put them in a spreadsheet. Then I used quadratic regression to best-fit the time offset of each beat to four smooth parabolic curves, one for each beat in each bar. I used the parabolic curves to calculate WAV files containing triggers to drive Elastika.
I think the trick might be having some way of separating accent notes that hit stronger from the regular notes, and having the synthesized drums reflect that shift in some manner. That gives at least two beat layers that interleave which helps with polyrhythm sounds, which may be lacking if you don’t have the accents. Thus one can do stuff like an accent that sticks to something like a 4/4 to glue it together, while the beats built on top can go all over the place with rise and ebb in intensity.
Of course I consider myself kind of a dum-dum on music theory (take it or leave it) – and I may not describe it the best, but it’s just a thought there.