Thanks for the feedback! :D
1. I reckon the green stuff is nice, but if you want a nicer/simpler background, YOU CAN EDIT THE BACKGROUND TILE. YES. YOU CAN MOD THE GAME BY CHANGNG THE FILES IN THE "Assets" FOLDER. Simply edit the tile/s in "Assets/Tiles.bmp" with a pixel art editor like LibreSprite (it's free) and colour the whole tile white or something. If you want, I can upload this as an additional mod.
2. That is not a bug. The shoot cooldown isn't capped. If you want, I can change it.