Thanks Len for the useful feedback.

I was going to say 10ms is about where I start to feel disconnected from
what I am playing, but I realize I am thinking one way and round trip
would be about 20ms. So 16ms might be well workable.

Psychoacoustic tests (many of them from the CCRMA SoundWire team and others) shows that 21-25ms is acceptable to keep a steady tempo. Larger values make the performers slow down, very low values make them accelerate! AFAIK in musical instrument design the 10ms figure is taken as a threshold for your instrument response (e.g. keypress --> sound), but in performance the values can be higher as said.

Your inputs are interesting, and yes, I think AES67 could be the first step towards integration.

More soon...

Leonardo