there is a way to send i2c commands to multiple devices but then you’d want a way to enable/disable specific devices, which would require its own op (or several).
an easier option could be having a 16n specific ops, something like
FB.ON channel note velocity. and for polling we could have something like
FB.CC channel cc (if 16n is running as follower). for the leader mode it could send notes as
SC.CV/SC.TR 17…32 (one for each MIDI channel) and then send CCs as
SC.CV 33…100 (sidenote, is there a way to prevent discourse from converting double dots to a triple dot?)