This is a really cool idea. Having to match the size of the target added a slight puzzle/strategy layer to the fights, and the snake boss was super cool. The SFX on bullet hits was a good choice too. It made it easy to tell when I had chosen the right bullet size without needing to stare at the health bar and take attention away from dodging. I also really liked how the camera switched to follow mode when you got super tiny. It really sold the scale change and made the map feel way grander.
Also, thanks for the gamepad support, it played really well on it! Fun jam game, and really clever use of the shrink/grow theme.