Partial Level
 

Hey heres a partial level for you to judge... mostly because Alt+1 doesn't work online, and partly because up and to the right isn't finished due to I'm still working on the tileset errors.
Anyways... Here it is

I filled in a little more already... I think it looks better than the first.
Something just doesnt look... "Right".

It's good, but you're clustering your details too much. It needs to look more random, not a clump of grass here, a clump of mushrooms there, etc. kinda thing.

I like it, I can't do it better :)

Clumps are a good way to portray a more natural environment. Now his clumps may be a bit too large, but it is much more preferred to clump than to just randomly lie stuff around the level(which makes the details seem generated). However it could use some grass in-between the clumps so that it's not so obvious, and like I said could benefit from having smaller clumps.

The cut swamp tile- theirs more than one tile for that, and it looks like you've only used one, try varying that

I see at least 3 different cut swamp tiles.

where

All for tiles should be there... I'll go back and fix that as well as make my clumps smaller