Now that we have a global metronome, I’d love to get a configurable rhythm gate (a filter that only lets hits through if they align with the beat or a subdivision). I’m sure it could have other uses too, but I’d love to have it mainly for practice. It would need a subdivision selector and an accuracy dial (percentage of the subdivision that you can be early or late for the hit to still come through).
Yamaha DTX actually has this, and it was awesome to practice accuracy (back when I had one).
Cheers 