Thank you very much for taking the time for such a thorough review!
Completely agree with all the shortcomings; the game turned out to be a bit more difficult to implement than I expected. In any case, I plan to continue developing games, so I’ll just take note of my mistakes and move forward!
Regarding the fact that at first there isn’t enough time to feed the mouth, I did this intentionally: you were supposed to drag it back to the start of the path while the mouth finishes eating the first character. However, this clearly wasn’t obvious to the player and should have been implemented differently. As for upgrades, yes, there are few items because good ideas started coming only in the last few days, and I wouldn’t have had enough time to implement them. :)