This is great, but there are a few inaccuracies regarding the lighting and how it is hitting her body. The light source here is a sphere, and the light it not blocked by any object or lampshade, which means the light is sort of going in every direction. Because of that, the light coming from the upper hemisphere of the light would be hitting her hair stronger than it is currently. It would also be bright on the bone structures of the left (our right) wing.
Because of the strong light, the shadows are also going to be stronger. It's all about the play of light and dark. If the light is hitting her left arm (our right) so strongly, her arm should cast a dark, solid shadow across her wing, but it doesn't. Her hair should also be casting a shadow over part of her face. Adding in shadows will help the illusion of light in this piece be more believable. A good rule of thumb is for every light spot, there should also be a dark spot in the picture. In other words, for every highlight, there should be a shadow. Right now, you have highlights and midtones, but no dark shadows.
This is a great piece though, and the choice of making the light source low adds a lot of very nice drama. Design and composition wise, this artwork is very strong! Nice work, I really like it!