This course is a pretty good course, pretty thorough, but I do have a couple of suggestions after playing with it for many hours.
All of the waypoints for the unloading points need to be moved up quite a bit so that they can accommodate a wider range of trailer and tractor lengths.
I would use the yellow secondary lines for all of the fields and the routes that are not main roads or paths.
I would make the areas next to fields where the tractors pull off the road to park next to the field longer so that multiple vehicles or longer vehicles can get completely off the road.
Otherwise, very solid work.