The artwork looks great! I love the way it goes from light to dark. The motion of the ribbon and wings looks great and very convincing too. The flowing hair add greatly and beautifully to the wind effect. To me it somewhat conveys that she is moving at a very fast pace and running away from whatever there is in the light. I love the overall color theme. It compliments the tone of the work and helps blend all the stock images very well. The landscape format adds to it too, like it could be a screenshot from a movie.
The only thing I could point out which might need working on is the positioning of the wing. The peak of the wing should be above the shoulder in the position it is in. Also, it should be moved a little inwards. You could also add a couple of feathers coming off but still a little attached to the wings to add to the effect of decaying wings.
Great lighting, great colors, great execution, I love it!