I was thinking of the way Dave Smith / Sequential do it, which is to have a full set of NRPN parameters, plus a much more limited set of CCs that duplicate some of those, making them useable with just a CC based MIDI controller.
Good idea / approach!
Alternatively, it might be practical to do a general numbered parameter via sysex or NRPN that's just an index into the patch data, like indexing an array. In which case, it wouldn't take so long to program, but it would still be a fairly large task to document it all, for the user manual.
while I generally agree, Sysex and Ableton is still problematic, as in, you can only do sysex via a maxforlive device. Ableton itself has no knowledge whatsoever about sysex (when it comes to external instruments)