I'm just going to throw a bit of critique;
1. The rain looks overdone and therefore distracting. Tone down on it a bit, and make it translucent if it isn't.
2. Swnging vines are rather pointless if you don't need to use them at all. It would be better if you would make the player require to use them. If you run at vines, if makes your jump from them higher. Psst, there's also a tilebug in that screenshot too.
3. Not really critique, though messing around with the events and characters can give you more ideas for concepts, without scripting. Breaking/exploiting the game for me can sometimes be the biggest inspiration.
4. You should put a down tube beside the coin warp room if you haven't, because some may attempt to walljump to get up there. Or Spaz golden jump, hard to tell.
5. The layout looks too straight and blocky for a natural tileset. There's a lot of repeating tiles. Mess around with the layout more.