a few thoughts
the bosses are WAY harder than everything else, especially the last one
a few more checkpoints might be helpful - I often fell in a pit trying to get a secret or something and having to spend ten minutes getting back
huge Yoshi's Island vibes, especially in the first two worlds (not a bad thing AT ALL)
just as polished as the rest of your games! shame this wasn't in a jam.
keep creating team bugulon, you're one of my favorites