Thank you a lot for your feedback !
Punch need indeed a better feedback, but I didn't have the time to improve it. Actually there is no "perfect zone" : you can get the maximum score by punching exactly in the center of the monsters, wich is quite impossible so don't worry if you can't achieve a perfect score :)
I had a lot of feedback on the difficulty of vertical monsters. I'll change that in a future update.
Thank you again !