-Is there really a point to even having the Chomp Rock near the end? There are so few enemies on the hill that it almost seems unnecessary.
-I can easily break your puzzle by hitting one of the other arrow clouds.
-You start a few tiles above the door as opposed to at the door itself.
-When you leave the bonus room with the arrows, why do you end up here and not at the door you originally entered from?
I can break both of these simply by throwing an egg. If you're designing a puzzle/challenge, you need to make sure the player can't bypass it entirely.
I'm still not entirely sure why you enter into this yellow stuff. It looks really weird and Yoshi stutters around in it.
Half of the coins in the cloud above this door don't even spawn.
Now that you've placed platforms, you can entirely bypass this whole pinwheel part by fluttering. You can reach both the secret room this way and the goal area.
The lava doesn't animate.
There are 21 red coins in the level, with the last one being in the arrow lift maze.
Come to think of it, I'm not even sure how good of an idea an arrow lift maze really is. It wasn't particularly challenging/interesting to navigate through, and felt more like it was blatantly tacked on just to artificially extend the level.
Overall, I still think this needs a fair bit of work. What I'm really noticing in your level is a lack of a coherent theme as well - that is, it still feels like a collection of small, unrelated areas. The level's name is "Boundary Between Life and Death", but I'm not really seeing this at all. Sure, you've used a couple ghost enemies in the last two sections, but that's about it.
When I first read this thread, I almost expected something like you having two identical areas, but one was live and one was dead (world 6's tileset perhaps?) and you'd switch between them via doors, but alas.