For one, the space aesthetic really gels well with the overall vibe and UI design of it all. I really liked the ambiance you went with for the game. The mission based clues you get when you hit gameover is a nice touch, especially for a project of this scale made in 2 weeks or less.
Now, I know you said that this game was intentionally designed to be difficult, I get that part. But the whole seed space thing can feel a little jank due to the gravity/pressure like movement. The way you had to shoot using the mouse can be a bit of a learning curve. I was able to get through it, though I wasn't able to get to the win condition because the bullet hell dodging can be a bit of an annoying factor to get through and I'm not very good at bullet hell, I must admit.
Overall, I feel like the design really catches the eye and I find the design of the mech cute,the clunky controls may have dampened my experience a bit but not bad enough for me to be frustrated.