Thank you for your feedback!
The chick's sound has 2 variety. Although after a few chicks, it blends together. I'll try adding more variety and adjusting the pitch :)
My reason for locking the other levels was to give the player a sense of goal since this is technically a highscore game. But don't worry if you didn't get to play the Hard Level, it's just a different map layout.
I'll keep those in mind and thank you again for your feedback and suggestions. It helps a lot.