A programmable step sequencer would be great, but I don’t know how it could be implemented. Ten exposed parameters per algorithm … 16 steps for just the sequencer values alone. I suppose a “page 2” graph in H9 Control is possible, but then how to translate that to H9 pedal standalone configuration? And forget about backward compatibility for stompboxes; it’d have to be an H9 Special algorithm only.
Actually, I’ve duplicated quite a few ADR III-type effects with the multi-modulation controls in ModFactor / H9. For step sequencing, there are a few ‘universal’ options, via the expression pedal input. EHX 8 Step Program & Source Audio Reflex, to name two. If you are so inclined, MIDI control offers even more options & variety.