Right now the head seems like a collage of pieces: eyes, nose and mouth all have different quality (eyes being VERY blurry). The face is too high, you generally want the eyes to be around the middle of the head, try to lower it a bit.
Other than that there's not much going on, so try to improve the quality of the face before moving on to complete the rest of the face. Hair can be tedious but once you get the pattern down it's an easy task.