It would be an original idea and way better than flying over the planet surface: Imagine an animation where the ship goes in the planet's atmosphere, you move inside your ship to a hangar with the vehicle, it would be a hab that you buy in the ship builder, then you are rocket-expelled from the ship, the planet gets closer and closer, then an animation starts while loading the next playfield, the animation stops and the real planetary playfield gameplay takes over and you are 'almost' seamlessly on the planet surface.
All this could be technically done with the current engine, and not even too much work for Bethesda. But maybe modders can do it? I would pay a good price for it