Fun and addicting! I enjoyed seeing my planet slowly fill up with turrets.
I like how turrets increasing their price incentivizes you to buy different kinds. I also appreciate the different enemy variations.
I think maybe add even more feedback for the main actions the player performs(think particles, screen shake, and hurt animations), you want them to be as fun as possible because they are what the player spends the most time doing.
The starting screen animation Is really nice, and the art is charming.
Cool game, the base gameplay is solid and has a lot of potential for expansion.