I think your lighting and color are perfect in this image. The low contrast and soft drift into shadow is sublime.
I think the body position is very strong: angled from the camera, but parallel to the light source. Those highlights along her back and legs are just heavenly.
The only thing I would do differently would be to have her head turned to face the window. Faces kind of take over a photo, and the lighting and pose in this are so wonderful, I think it might be stronger to force the viewer to just focus on them, and leave identity to the imagination.