With the main light so far off to the side and little or no fill...it's got a very artistic or edgy look to it...and as such, it's hard to offer critique. Either you pulled off what you were going for, or you didn't...but without knowing what you were trying to do...we don't know if you accomplished it or not. Do you know what I mean?
I like the hair light and the separation it give her from the background.
I agree that it could use a bit of 'pop'...whiter whites and more contrast.