We now have two types of non-aquatic mounts: ground and flying with flying as only steady (Helicopter) or skyriding (Airplane)-- but not both at the same time. Some mounts are clearly helicopters: some look much like them and some should behave like them (magical as in flying carpet, disc, the headless horseman mount running in the air, etc.). Some are clearly for skyriding with wings and the obvious need for vigor.
Why not all three at the same time? Let the skyriding toggle determine whether the airplanes behave as helicopters, but always let the helicopters be helicopters where flying is permitted.
I love skyriding and I love steady flight. I think this solution will please everyone and will let the love abound!
Just a thought.