Hi, thank you for all your comments and suggestions!
I agree the the game is too simplistic in it's current state. If I ever come back to this project I would love to add things like a win condition, upgrades, better spawning system etc. I think the game's clarity would benefit a lot from extra colors, so potential updated version would certainly be more colorful.
Even though the game itself is not up to par with the competition (there were a lot of amazing games here), I'm still very satisfied with the project. Algal Bloom was the first game I ever submitted to a game jam and it was an awesome learning experience. I'm really happy that I managed to upload my project in a playable state, and some of you guys spent a moment to test it and share your opinions.
Cheers!