A great tone and one worth striving for in the print. This shows her in a natural context and reinforces her relaxed look. The crop is OK but looks more posed because you have nothing to relate her expression to.
I think if you crop the top so that nothing above the railing (the darker stuff) shows, in effect a closed landscape type of arrangement, this will enhance it a bit. Then, if you crop the last right vertical post, so that there is just the darker section no white, but leave all of the chair, then you may find it is more focused on the subject, her face then becomes the centre of attention with virtually no distractions. Very nice this one, and I believe it may be more nice with a little cropping. Mick.