To make Scaler more adequate for jamming live, make an option to click on the sustain pedal to move to the next chord in the progression.
My tests have shown that if the time between sustain-on and sustain-off is less than 500ms, it can be interpreted as a click. That way it’s still possible to use the pedal for actual sustain.
Maybe also offer other midi events as an alternative, eg. modulate/pitch: up for next chord, down for previous. Let the user decide what fits.