Well, here we go. You asked for it. ;)
Because you have a large amount of tiles, I going to critique most of them in groups, rather than raating them by each individual graphic.
Anyway, I am going to begin with tileset one. The small grass, bush, flowers, signs, rock, and cut tree are okay. The grass has an awkward patter that doesn't look very nice when it is used to cover a large area, mainly because of the empty corner in the lower-left of the tile. Try adding in some more light green there. The wind Pokémon grass needs some work. While that style is can look good, it needs to be rearranged in order to do so in a large area. What you could is take the one of the four wild Pokémon grasses from the tile and align it to an 8x8 tile rather than align all four to a 16x16 tile. That way, all you need to do is take four of those 8x8's and arrange them to make a 16x16. Besides the allignment, these things need a shadow, or a more prevalent one if one already exists. That way they don't appear to be hovering. The flowers are pretty decent, but the leaves need to be worked on. Try making something that looks like ellipse, but with onse side straighter than the other for a leaf. One other problem with the flower is the one flower that was rotated. It just looks odd at that angle, and would probably look better if it was rotated back to the angle it was at. For the whit sign, it could use some work, also. For one, the shading is way off. The brightest spot should be at the top, not on the side facing the player. Now, you should of course make the area where the text is supposed to be brighter than the rest of the side. The sign should also be a bit bigger, so you can make some fake letters to put in it. This way, the sign looks like it actually says something. The bush, the rock, and the cut tree are fine the way they are, as they are edits of Nintendo stuff. Now onto the paths and stuff. In general, all these tiles have a boring border. Try adding the regular grass pattern in place of the solid green there. Also, try a 2-pixel wide outline of the darkest shade of the grass to each one. That way, the transition is much smoother, the paths/waters look like they are actually a part of the tile. Once again, there is the hovering issue. Now, onto each individual one. The light green path has one thing wrong with it, aside from the other issues: it has no texture. For a beginning texture, I would suggest you base it off of the standard grass tile. Don't use it, but use it as an example. This way, your style will also be consistant. The dark dirt pathcould use a little brightening up, as well as spots of an additional shade of brown.This way, you get a much better texture. The sand tile is similar to the dirt one, except you should darken it a little bit instead of lightening it. Yes, that also means you should add some of an additional shade of brown. For the brick path, if it is eroding away, I would suggest you add in some bits and pieces at the edge. If not, try giving it a more defined border, which could be done with bricks of only the light color. The first water needs some work, but this one is a little tricky to do, anyway. You should make it look like the grass is overlapping the grass, rather than sitting on top of it. To do this, you are going to want to make the bottom half of the brown area only about 1-2 pixels thick, with the grass overlapping it in some areas. For the sides, they should be 2-3 pixels thick, the grass once again overlapping in some parts. For this, you are going to want to use the dark brown underneath the grass pixels that are overlapping and lighter brown elseware. Now, the top part should be about 4-5 pixels wide, the grass overlapping it in some parts (once again). As I said before, use the darker brown underneath the grass, and the lighter brown elseware. For now. In addition to this, a third, brighter shade of brown is needed for this part. All that needs to be done is to use the paint bucket tool to fill where middle shade of brown was. Then, use the middle shade to transition between the dark and the light, and to create cracks and crevices. If you want to, you can also use the darkest brown for the last part, too.
Well I'm sorry I couldn't rate everything, but I got to go. I'll edit this when I get the time to critique everything else. But see, I told you I wrote alot.
