It looks as if she were floating above the surface. It's a very gentle and subtle dance, the way the model is posed and the colours make it seem this way. I like the touch light at the left bottom. It's beautiful.
Where is the lack of focus coming from? That really kills it for me. Cool concept although it is basically the same construction as [link]
Also what did you do to the skin tones? (I see that hers is like that as well) The light blue makes her light skin become a bit lost. Perhaps slow your aperture and snoot a strobe at her from above the water (maybe two, one for upper body from one side, one for legs from the other) Then you could have her lit with that white line edge definition from above, maintain blues and limit the over exposure of the water.
Going to the Galapagos Islands!!!! It's on my wishlist!! Lucky you, I'm sure you'll have a great time there and that you'll be back with lots of fantastic captures!!! Looking forward to see them!!! Take care!