Going off what Lenh said a little more, your sprites certainly aren't bad. You know angles which can be tricky for some people.
You just namely need to clean up places where difference parts from different sprites meet. The collar and bangs on the first splice, the choker of the second splice, the area where the helmet meets the face on the 3rd splice, and the bottom of the near hair on the final splice.
Overall though, you're on the right track, and I'd like to see what else you can do!