I really appreciate the feedback and I'm glad someone pointed these problems out.
First of all, I knew (sadly, only after submitting) that the game is way harder than I meant it to be. Mostly because I spent a lot of hours making it, and thus getting familiar with how it works. After the jam, I will definitely slow down the snake.
I'm really sorry I didn't manage to communicate the snake's instincts well enough. Although I was more or less aware of this, I didn't really have time to fix it. This is mostly because of my poor time management.
However, most importantly, I'm really happy that you liked the game despite of its flaws. Seeing in-depth critics ending with "I like it" just feels amazing. Thank you!