I really like the direction of making a puzzle game about waves! Puzzle games are incredibly difficult to make during a jam since they require so much play testing to tune, but I think you're off to a great start with this one. You've got good mechanics, great vibes with the music, and good quality of life features like the skip level button and fast one button level reset.
I think the biggest thing that would improve this game is an adjustment to the controls. I think that you should use A and D for both movement and aiming the wave since the character is locked in place while aiming anyway. I would also include a key to cancel aiming a wave once you start. I would often unconsciously tap space bar to jump and trigger the aiming.
Awesome job!