Make it a full Mount ability.
Remove (or keep, doesnt matter) Major expedition from the skill

Make 1 morph increase mount stamina regen, and decrease the cost while sprinting on a mount

Make the other morph also add minor galopp, increasing mount speed even further.

I think this will be a nice change, as pretty much no one uses the skill for anything except riding speed anymore, due to the extreme cost, and low duration