fly around an asteroid field through pathways and find "clearings" which contain enemies all the while being chased by hunters, groups of powerful enemies who will try to track you down.
would probably require zooming out the game
hunters could work on a knowledge based system under the hood, they gain knowledge over time and lose it when the player moves (not all of it)
there could also be scanner drones which hide in rocks and also come in that you have to hide from and if they see you or are destroyed the hunters gain a lot of knowledge, not enough to spawn but perhaps increased to ~90% ; ~70% if destroyed, which means you have to go quickly for a while [if this doesn't get in you could keep this enemy and have one occasionally appear and when it detects you it just summons a powerful foe such as an eclipse (scaled to your level)]
[if this doesn't work it could be a celestial hazard, a barrage of asteroids move across the screen with a path that you have to navigate]