One chord / inversion per quarter note without hesitation. So for example I might do c7 1st inversion 2nd 3rd 4th in one bar, then f7 1st 2nd 3rd 4th next bar etc… chromatic, in 2nd, in 3rds, mixing up the order of the Inversions, just playing a single inversion per key, etc… but always one chord per beat. Sometimes I’ll put on a beat and do some « real » comping with rhythmic patterns to mix things up, but I mostly want to drill the chord shapes first. I use the scale drills / arpeggio drills to learn the actual note names more than the chord drills, although it seems to all happen organically.