I haven't had the chance to do photos like this. I can't wait to try!
I have a friend on facebook that does fashion shots all the time. I remember he critiqued a photo once, much like this and it made sense to me.

I think her front arm doesn't look natural with her body flow. I think, I would also like to see her chin, a bit of space and then her shoulders. I'm picturing it in my head but maybe that is where it should stay.

That is a wonderful gift and moment shared between the two of you. If anything..that makes the photo wonderful!