Just finished testing it, and it's a pretty good level for the most part. I did find some issues though.
Getting past those volcano plants turned out to be a rather blind jump that gave me almost no time to react to the enemies ahead. I died to a kicked shell on the first try, and bumped into the koopa on this try.
WOAH! Odd place for an invisible coin block... (I know it leads to a Yoshi Coin)
This is just me being nitpicky, but how many people do you think would find this spot strange enough to try jumping?
Trying to get this particular Yoshi Coin borders on Kaizo treachery (it's a disco shell for those of you wondering).
Again, I'm being nitpicky, but I really don't like seeing enabled Switch Blocks being required to obtain a Yoshi Coin. If a powerup or 1UP sat there? Sure, but why should I collect the coins if even one of them is inherently beyond my reach?
This area incurs a lot
of slowdown. Try trimming down on the sprites here.
Depending on where the screen is positioned, players might not realize there is a kicking blue koopa up there. On the other hand, standing in a place to shift the screen away from it would usually keep you safe anyways, so this could be a non-issue.
This reminds me of an issue I had with an earlier rendition of metalgearhunter's level: you're essentially forcing me to pick between a powerup or stage progress. It's practically impossible to get the powerup AND still be able to hit the ON/OFF switch (and vice-versa). Consider revising this setup.
Uh... what threat was this Diggin' Chuck supposed to pose again? (I came from the right side by the way)
...and now I'm in an endless bonus stage? Does that mean you intend to make this stage even longer?!
(Mind you, I think this is as long as it should be)
Whew, that was longer than I thought, though some of it is just my nitpicks, so take it however you see it.