Very good art and mechanics!
I had a similar idea, but decided to abandon it because of the complexity of implementation, I'm glad that didn't stop you.

Cool mechanic! It felt very natural. I also agree that some background music and additional sound effects could go a long way and make everything more polished.

The mechanics of switching between the persona dn the animal worked great! it captured the theme well of having the person only able to essentially be a vehicle for the smaller animal to go do objectives. I like the aesthetics of the game and the animations of the players. I would recommend adding some music and adjusting the jump sound effect as it became repetitive and kind of annoying by the end.