What sort of display were you planning for the rover interface? For the jam, you could have cut the upgrade system for working on the rover interface to allow for a game loop of sorts and then added the upgrade system later if there was time???
From the screenshots you posted, it looks really nice, I am definitely interested in looking at it when you finish it. I imagine you had planned some kind of resource analysis, gathering and management to lock the rover customisation behind game the gameplay of exploring the planet(s) with a rover?
It's a shame you didn't pull it together in time, but if my imagination us accurate with what you have already been making it sounds like the kind of game I'd enjoy.