Thank you very much for the great feedback. I do want to make some improvements and changes to the game if I have the time.
If I do so I will definitely do something to make camping less effective. Either by spawning enemies in your corner of the arena or by rewarding an aggressive play style in some way.
Difficulty is also something I want to work on. I might increase the enemy spawn rate, make the enemies more dangerous, add some new Enemies, and or decrease the spawn rate of the health pickups over time to make the game more challenging.
A scoring system would definitely be a good addition and should be very easy to implement.
Moving enemies into obstacles sounds really interesting. definitely something I want to try. could be it's own game mode