My idea which I don't see suggested much: More to do with a spaceship.

[Chesssx]

I don't just mean construction. It would be cool if we could make fully-functional spaceships with hydroponics and solar panels. It would be awesome if after launch you can do things in space. There could be events in an FTL style.

There could be a whole storyline in space while still keeping a RimWorld style. There could be pirate raids where they shoot from a distance and you have to shoot back with cannons. Colonists would have to do their best to fix the ship.

Maybe the colonists could go into cryosleep for a long time with the ship set to wake the up, but the ship malfunctions and they wake up 5000 years in the future and everything is different. That would keep the game generally the same while adding much new content.