I like the mechanics on how the game works - like how if you go off one side, you come back from the other. The movement also made it more chaotic!
Besides that, I believe that some more enemy types would be fun, maybe a boss/mini-boss? Maybe also cap the fire rate at something (if you didn't), because it seems I can fire at 14 clicks per second, which may be a bit overpowered. I'm trying to rate a lot of games, so if you could rate mine that would be greatly appreciated!