Short but fun game. As others have pointed out, the skill tree felt unnecessary for me because I was already getting what I wanted.

The game could be updated without having to even add new content if you just make something like the scaling a bit harsher so that people feel it's worth upgrading in the skill tree.

Equally, the skill tree could do something like open new options for critters or further down the line, it could open up a new world, maybe it opens up the underground or whatever.

I enjoyed playing it though, nice game.