Criticism -
Some of the enemies were a bit difficult, mostly the triangle one with the blocker. It was far too easy to get cornered by a couple of those things and lose all of your health. Also, bullets generated by enemies not damaging the other enemies, like the boss, feels unfair as you have to contend with your bullets and their bullets while they only have to deal with yours.
Support -
I liked the simple art style, very in theme. I also liked the sfx, they were very satisfying and they made it feel good to kill enemies.