I like the portrait a lot Vans. There are some things that can done to make it better. The top of the head lacks lots of detail. Add more details to it. Sprites need a lot of details added into whether big or small. As for the skin tones, looks like you've added too many tones. I would reduce it. Another thing to improve the eyes is add a color below the pupil to the iris of the eye. Here's my edit.