I think you can do that now, for instance I’ve also mapped my Maschine Mikro Mk3 to send note data to the Misha, alongside my midi keyboard.
On my picture all of the white keys to the left of the default mapping, I’m going to make the first octave the KEY select, and then the remaining keys I’m going to make CHORD select. I think you could do this using a secondary controller too, just like the NAMM 2022 video that Steve did, he was using a Novation Launchpad I believe to select the KEY. Perhaps it’s because the midi routing is going through a DAW which makes it possible, but you can probably do the same using 5-pin DIN MIDI thru.
And an idea for your V-drums, perhaps you can change each pad to only have say 3 or 4 velocity layers in the drum brain, and then have them mapped to different MIDI notes, so you could get more functionality out of each pad. I have a TD-20 in the basement, and your video makes me want to break it out, but I’m already waiting on a Torso T-1 to arrive which I want to merge with the Misha first. My idea is getting the Torso T-1 to handle “backing track” duties, and then somehow use the Misha to send MIDI CC or note data to the T-1 to control all of the melodic tracks in the T-1. So the idea is I select the Key and Scale on the Misha (using my MIDI keyboard), and this will change the Key and Scale of the T-1 melodic tracks, so I can effectively jam out like you can with a modern Casio keyboard with their “backing track” feature, where you can have a small ensemble playing loops, but you can change the key they’re in using the notes on the left-side of the midi keyboard.