Have you considered having some ships require a rocket-style takeoff in heavy gravity? Do you literally just point straight up and take off if they're too overladen or the gravity of the planet requires it?

You can sort of do that now already. In some ways it's a more optimal VTOL. The problem is a lot of the ships are not really designed to sit on their tail. Again, using the Reclaimer as the example at the moment in game, when you're in VTOL mode, you keep up, and then you see this weird dance where they try to get high enough to go out of landing mode to put the engines back, whilst aiming as high up as possible, and kicking it into normal flight just before they hit the ground.

I think I would much rather you do a run-up and get lift off of your wings and then pull up and carry on like that than just sitting on your tail and taking off. The ships are just not really designed to do that. They're going to struggle.