The whole trick is that to make the EVO pilot work
well if you want) the most important is PGN 126208, which is the general "I can transfer pretty much anything" PGN. Similar for other vendors.
This makes the autopilots a prime example of devices that most benefit from implementation in a plugin
with architecture similar to the current radar plugin
(= one implementation of the underlying shared stuff reasonable extendable for the different products).
Better architecture than trying to do this in the OpenCPN core
and sure much faster to yield usable results.