Programmer here. Thank you for your feedback!
Honestly, I like the fact the game can go as far as 30 levels - I really like the chaos XD. But for the content we managed to add, yeah, I agree, 10 to 15 was probably enough.
30 levels would only be truly justified if we added more entities and more content in general to the game.
Again, thank you for your comment and I'm glad you liked what we cooked :D