This is nice! I agree about the strap though, I would have asked her to take that off. Maybe you can clone it.
This is a beautifully simple shot. The only thing I would fix is the small scar on her forehead. also, that strap on her shoulder is distracting...it may be more stunning in black and white but in color is beautiful too!
Your choice of butterfly lighting is kind of unusual, and I think another scheme might have looked better. Did you make any different shots?
Also the strap. BTW: if you ask a model to unshoulder her bag, watch carefully for any slight change in her posture that results from her holding the bag in her hand. Make further suggestions about where she holds the bag if you see unusual posture.
I do like the background.