First off I want to say that this looks amazing. It was defiantly worth sticking with it to finish this picture.
I personally love the way her clothing looks on her, it drapes well and the fact that it’s transparent makes it look perfect for a fairy. I like the shape of the wings, but I think they could have been a little more soft and transparent. I agree with you on the rocks as well, I think you added the perfect amount of red-brown to it to give it that real life look.

I like the hair all the way up until you get to the ends. They seem kind of clumpy and stiff, and all end at different lengths (which I understand can be from her hair being up). It’s very difficult to get the ends of hair looking otherwise, but I think with a little more work and a few more tutorials you could pull it off.
The hand is kind of chubby, stretching out the fingers would be a good idea. Also the position of her hand doesn’t match her arm. Because you can see her elbow at a perfect angle her hand should be turned with her fingers facing down, but not turned too much. If you turn it too much you’ll run into the same problem.
Now onto the water. The reason the water doesn’t look right is because it’s too soft looking, I think it needs more solid colours. If you want it to look murky you could maybe add some brown to it to show the dirt in the water.

All in all, I think this is your best work yet. You did a fantastic job and even if you don’t make all the changes I suggested, it will still look fantastic

(I also give you permission to ignore my star ratings. I'm not sure if I understand what all of them mean haha).

I'm always fond to find an artist who has ventured out of their comfort zone to try something different; it's always important to challenge yourself artistically and far too many artists simply stagnate themselves.

As far as this work is concerned, I did a quick comparison with the other contents of your gallery and it's pretty evident where you treated certain things differently; the hair and coloring technique seem to be a departure from the way you treated them in other works.

The level of realism is pretty decent with the anatomy and proportions being well done, however I don't think that the subject matter meshes well- in my experience I prefer that fairies have a "lightness" to their form, sort of like the sense of being fragile which you get when you view a butterfly. The style of realism which you've used makes this particular fairy seem more "heavy" and more like a human with wings rather than a member of the fey folk but it is certainly an excellent starting effort.

I might also suggest that you experiment a bit with making your shadow areas a bit darker and your areas of reflected light a bit brighter. What I've personally found is that when the areas of shade and light are too close in value the image can seem a bit washed out and a little 'flat', which isn't necessarily a bad thing- just different. You may want to dabble a bit in heavy contrasts and see if you like what you see in the results.

Water is extremely difficult to "get right", I know I've never quite done it myself, but you've done really well considering that I haven't seen much else in your gallery featuring flowing water.

The sense of scale is a bit off, which is to be expected. My first impression was that the fairy is the size of a regular human and it wasn't until I noticed the long grass blades in the background that I realized that she was supposed to be the traditional tiny size. When I think about what gave me that impression I have to say it was the inclusion of the stones as they tended to draw my eye away from the grass and I immediately thought of them as larger river stones rather than tiny stream-side pebbles. I don't really have any suggestions as to how to give the proper scale at the moment except to maybe try to feature something else in the foreground which will convey the proper sense of scale.

All in all it's a really good effort on your part and I really hope that you experiment a bit with contrast and continue to venture out of your comfort zone.