First sorry for my bad english and maybe my idea is difficult to explain.
With Rhythm patterns and Groove patterns you can configure gate, velocity and delay into a pattern for each step seperately. This is great but also a little uncomfortable (sometimes ;-)).
In most little drum machines like Volca Beats you can use a kind of live mode where you play/drum live on an instrument and it is directly recorded to the sequencer. So in Midicake Arp: wouldn`t it be possible to record and transform a live played rythm (One knop on device or external drum pad) to a rythm/groove pattern? This would really help me to create intuitive rythm patterns on the go(groove patterns I don`t use very much). Hopefully my words make any sense.
I suspected it couldn’t fit into the philosophy of the Arp 🙂. Maybe this kind of live recording requires a new kind of live sequencer data structure beside rythm and groove.