The old Yamaha RM1x had an unique feature called MIDI Delay. It produces the note delay (echo) effect, but obviously not in an audio signal, but by creating additional MIDI notes. You could set various settings, including the obvious ones like the length of the delay expressed in the number of sequencer ticks, initlal volume and the number of repeats. You could also set the feedback parameters, which were the offsets by which every further repetition was changed - these included velocity, note value, gate time and clock shift. Then you could render (record) its results onto the pattern or just use it as a performance element.
I think it would be very interesting for the Oxi One to have something like this available, at leats in a partial form.