Cool idea! I was a bit confused on what all the buttons did even after reading the tutorial and wasn't quite able to figure them out while playing either. I do also wish there were some more pressing threats to my berry as well. It seemed that I could just keep it in the incubator forever.
Nice job trying out UI! Godot's UI system is kinda scary (at least it's scary to me :p). Also, I really liked your pixel art for the berry.