Speaking freely, there are two things that are bothering me: Like Adp001 said, the shadows. The shadows on a sunlight day are much darker. The sharp edges of the shadows are allright , that's what you expect from sunlight. I think the AO could be stronger to make the shadows in the deeper parts darker.
That's one.
Second: I really think the skin of the body looks perfect, but the skin of her face, looks rather flat to me, just like she used to much powdercoat-makeup, perhaps you can give it a more oily appearance, which won't look strange on a beach.
I hope I didn't sound too hard, I have great appreciation for your work, it's always a pleasure to read your threads in the node-cult.

Bopper.

-How can you improve things when you don't make mistakes?