What Would be a good Obstacle for a shooting sim

[Temeraire149 (Temeraire)]

I want to make a fps game in space. Heavily inspired by Ender’s game and Echo arena
What would make a good obstacle/cover for the arena?

Enders Game - Battle Room

Echo Arena | The Most FUN I've Had In VR...And It's FREE!!!

I find pretty boring those rotated cubes/pyramids
What do you think?