Found everything except for one flower. What I found:
1 in the first area/sublevel
1 in the cave section
2 in the final area
No clue where I missed one, though I'm wont to believe it despawned. Read up on this section of the FAQ about how Item Memory works. A lot of your collectibles are in areas where they can be easily despawned.
1. Starting position is seriously glitchy. Move it down a few tiles.
2. This bush isn't actually embedded in the ground.
The Nipper spores placed above here are super unfair because they don't even spawn until Yoshi is about to collide with them. They're impossible to avoid unless you scroll the screen up beforehand, and there's no way for a player to know about that playing the stage blind.
I feel like you could make use of the Nipper spore generator sprite here to make things more interesting.
Carrying the fire melon all the way over to these ice blocks seriously sucks if you haven't cleared it out beforehand, mostly because you can't use your tongue. I'd recommend moving the melon to somewhere closer to the actual ice blocks.
Also, minor gripe, but I don't like the fact that the player isn't able to backtrack beyond this point.
Awful lot of egg use required here for somewhere without a readily available source of eggs, no?
Also, I thought that this spring ball would lead to a warp when I first came across it. Make it more obvious that it's not a warp.
I really don't like it when a stage presents me with two options and one of them is a point of no return. It's not really clear at first whether the above example or the pipe leading here is the way forward.
Place object 33 behind this water to prevent players from swimming under the land.
1. What's this pipe for?
2. The bottom-right coin causes some cutoff when you collect it.
3. Was there supposed to be something in the bottom-left corner of this group of coins?
One of the pipes in the cave (in the room that leads to the final section of the level) doesn't have a screen exit set for it, causing me to show up at (0,0) in 1-1.
A couple of other notes about the cave:
- I'm not really fond of the wingless skeleton goonie spam, especially if they blindside me when I scroll the screen.
- I don't feel like I'm given enough time to react when I first come across a piranha plant concealed in the crystals.
Yoshi appears behind Layer 2 upon entering this room.
A lot of your ledge edges aren't properly connected to the ground.
You have 21 red coins in this stage.
Minor gripe, but I don't like how I can't backtrack from the goal ring area. Not really that major considering that I can't backtrack from this sublevel anyways, but still.
Overall, not bad. I definitely like this a good bit more than your other stages.