The clouds in the background and the overall shading in the entire image is beautiful. More specifically, I think you did a wonderful job shading her "outfit", also the shading on the ground is practically flawless as far as I can tell, and I also like the way you shaded her legs. Plus the pose is adorable! She looks so carefree, like nothing can bring her down. Though, I personally think it would be a little difficult to stand on your toes like that for very long.
Though this is totally awesome, there are a few anatomy problems. The hands and feet are too small. Hands are usually about the size of your face,though in anime and cartoons that's usually exaggerated to about the size of the entire head. The feet are about right, I think they should be just a tiny bit bigger, they should be about the size of the forearms.
The eyes are also a little on the big side, but I noticed that's a trend in your art that makes it very unique and gives it your own little flair, so I like that in your art. Gigantic eyes are actually harder to pull off than they seem, and you do it quite well!
I noticed in your comments someone said that the boobs are too small, but they actually look just fine. Not all girls have DD size bras they can hardly contain in their shirts and that's actually another thing about this particular piece that I like.
Overall this is quite the charming piece and I look forward to seeing more from you in the future!