Enjoyed the powerup system, it felt nice and had good feedback. I think the fire rate stuff was a bit buggy, sometimes I shot streams of bullets with basically no restriction and sometimes I shot just as often in the small size as the big size, but I'm not sure. It changed only after I grew/shrunk a little bit at a time.
I think having the size of your player affect gameplay is a cool concept! I wish I could have seen more concrete/explicit use of that mechanic besides just the damage and fire rate, because it's a cool idea that has a lot of room for building around.
Congrats on the submission everyone, and well done!