I enjoyed the game. The rocket launcher feels underpowered & some weapons run out of ammo too fast. Besides that, this top-down shooter is pretty cool.
Some other fixes I'd suggest are to prevent enemies from spawning too close to the player at the beginning of rounds, show ammo count on the cursor (where we're looking at to shoot enemies), and add a few seconds with no clickable elements at the end of rounds to prevent buying upgrades by accident.