IMO a gun overheating mechanic and increasing difficulty would make it a full game.
Holding down fire to spam and sweeping the gun back and forth creates a wall of bullets that eliminates most of the asteroids right as they appear and sweeping towards the fastest asteroid easily catches any stragglers, completely breaking the mechanic.
Holding down fire to spam and sweeping the gun back and forth creates a wall of bullets that eliminates most of the asteroids right as they appear and sweeping towards the fastest asteroid easily catches any stragglers, completely breaking the mechanic.