To me, her head seems so small compared to the open space around her. I wonder how this would have looked if cropped to be a vertical image? Your title is interesting...but to me violet is purple and not blue. I do like the blue and the highlights on the hair though.
There is a lot of depth in the expression of the model. I can't exactly put my finger on it, which kind of works as it leaves a bit of mystery into what she was thinking. As far as lighting and composition, I personally think you missed the mark. If I were taking this, I would have avoided the shadow across the face and the white area on the left. Also, I would have placed the model off center and up further to include more of the shoulders.
I like your original image, but it's a little bit flat and the white is distracting. I wish I could see more detail and brighter lighting on her cool hair.