Are you using an Art Magic hack like I’m proposing, or just adding new skills?
Yeah, I’m definitely wary of just jumping in with new homebrew subsystems. Of course, there are a lot of ways to work around the lack of a space combat mechanic. Like not giving the players’ spaceship any guns. Or, more realistically, not having spaceships in the universe to begin with, because if someone in the universe has a spaceship with guns, then the players will probably find a way to commandeer it.