A biplane vr sim would be fun, there’s plenty of interactions to dive into, like adjusting the engines and clearing gun jams.
I’ve long wanted a single person tank/artillery simulator and guess I’ll just have to build it. Something about choosing a target and ammo type, grabbing shells from stowage, opening the breech, slamming it home, driving a tank and standing in a cupula just have vr interaction fun written all over.