I think the feature in section A where is captures midi notes and chords could be useful to copy down to the pattern mode and it would consist of single note presses (melody) and chords. These would be assigned to each step in the pattern. Then based on the scale we choose it would adjust notes and chords to “fit” we could of course use section B to substitute as usual.
We could overdub by selecting a step and recording a new note or chord for that step.
Probability per step and tie (glide) could also be added
Of course add play direction (Froward, back, random) and speed. and we have something here
Once we have the pattern we could drag it out to DAW as midi.