Add black holes!
They eat any nearby stars and even the player if they get too close!
Enemy rockets also are affected by them.
If you get eaten by one, it's a game over.
Nice. Another "tip"
Something makes the game extremely laggy, at 10 stars+- game goes in 10 FPS.
Back to "tip"
I think about something bullet hell pr power ups like immortality or magnet.
Also ability to shoot enemies, maybe.