Anyone have sets of exercises they do for practicing buildups, rhythms, leads, chord progs, etc? What are they?

I like to take 3-5 samples (anything) and do five channels worth of "add fx + flatten, repeat" on each of them. I turn them into risers, 100% reverb things, weird distorted sounds, anything.

Similarly I'll take a bunch of random hihats, snares, toms, and misc percussion elements and arrange short loops out of them.