This is a neat little level. The overall design was fine, but there are a few small things that bother me:
- The first section feels a bit crammed. This isn't that big of a problem, but if you're big and have a kuribo's shoe, you will get hit by some of the spikes on the ceiling (The ones above the second to last venus firetrap together with the green piranha plant).
Edit: I just realised that you don't get hit when you duck, but it might still be a good idea to remove one spike.
- It isn't very clear that you can fall down in the bonus room. You could have another exit in the top right purple pipe, and let the feather be another bonus. Or you could place some extra coins to indicate it's safe down there.
- The second half is really short. I liked the idea of the section, so maybe you can expand on it a bit more. And you were a bit too generous with the kuribo's shoes (I get it that you want the player to have a second chance and get another shoe, but it was a bit much).
I'm also not sure if the level needs a midpoint, but it doesn't hurt to leave it there.
-Made some of the ceilings higher so it's not as tight.
-Made coins below the nippers in the bonus room so it's clear you can fall.
-Made the final area longer and there's fewer Goomba Shoe pick-ups so you're penalized a lot more for getting hit.