A basic “tilt” style EQ on a single knob, or a base/width filter like a Digitone would be handy - would free up the resonant filter for creative uses only instead of having to compromise between using it as a resonant filter or an EQ…
Alsoooo… I’ve said it once… I’ll say it again… polyphonic playback of samples and increased pitch up/down control that also doesn’t ruin your chromatic keyboard range…