Good luck adding more contents for your game in the future. I even did it to my old game which was from old game jam ;).
Played your update. Nice start for improving your game after game jam ;).
Some thought again when played the game:
- The Shoot and Skill keys are a bit awkward for the distance, especially they are both important. Should try with Z and X instead.
- About new ammo bar, should make it appear only after picked up a new weapon
Also a question, why not making the wave attack killing instead of pushing? It would make killing crazier, but with cooldown to balance it ;).