Hey @core.east there’s an ongoing driver chat thread here. You should post in there so others who have been working on (or interested in) driver development will see the discussion.
I’ve also been working on the apc 25 driver trying to adapt it to the launchpad pro (mk2) for Oram. I got 70% of the way but the sequencer ‘notepad’ input functions never worked. The Launchpad doesn’t have any keys, only buttons (similar to apc40) so there’s something in there that needs to change to allow it to work.
But as discussed, an abstracted sequencer class avoids having to reinvent the wheel for every device.