Thanks for your huge feedback!
Apart from level 1, both 2 and 3 are much harder than first. It's not mandatory to fail, but might happen if you're not trained to the genre (or you've a sort of undiagnosed ADHD like me :D).
Regarding the music, we tried to focus on the suspance and the "ticking" concept. It's cool to hear that not everybody enjoyed it, thanks.