very pretty eyes - i like the pose and the relaxation she shows to us - but I think a bit of cloning or watching the hair fly aways would be something to consider here
First impression: Your model looks very comfortable in front of the lens and shows a natural smile. The tight crop really makes this photo as all my attention is on those beautiful blue eyes.
Suggested improvement: I wish the bg were pure white instead of having a blueish hue. I think it would help to make the blue in here eyes stand out more.
I might have cloned out the hair on the sleeve of the arm as well, but I am not sure I would have sharpened the shot anymore than it is now. everything appears to be very sharp to me (warning: one of my problems is not sharpening enough - so I could be wrong, but I don't think I am)
Nice pose, great smile, good job with the lighting.
Very minor suggestions: a) do a tiny bit of selective sharpening on the eyes so that they match the sharpness of her lips and b) if you have time to spare clone out some of the stray hairs near her arm.