It’s probably the best thread we’ve got!
Nobody’s worked on that yet; the whole thing is very much engineered around CCs, and the current way the data is stored in EEPROM is… highly CC-centric.
It’d be relatively easy to fork the 1.3x firmware to investigate MSB/LSB CCs or NRPNs; working out where to put the config in 2.x would take more work, as would updating the editor.
But it’s a reasonable request. I don’t know of anyone who’s implemented this so far, thooguh.