I gathered an idea today based on the airport size restrictions. The idea is basically if an aircraft has its destination airport set as an airport that is too big for the aircraft, a message is prompted that says that the aircraft is too large for the destination airport (no gates at the airport are large enough for the aircraft), and the aircraft cannot fly there, and the destination airport is taken off the flight plan. If the aircraft continues inbound, another warning is issued. If the aircraft lands, a system ghost or a violation is reported. This would only be for the Training and Expert servers.
This feature request may be subject to change in the ghost/violation section of it.
Sorry if this is a duplicate topic, I don’t know what to search for in the search bar if it is.