Excellent shot, Jim, my friend! (What else is new??) My only critique might be that I find it a little pale, but that is neither here nor there. More to the point, the lighting is great and so is your model. Knowing what I do about the violin, her position is quite lovely - obviously someone who has had some good training. Believe me, I've seen so many contorted, inefficient, wretchedly trained violinists that it is a rare joy to see a photo of someone who, for the most part, does it right. Of course, I am of the old school who thinks a shoulder pad only makes one struggle to produce a good violin sound, but in spite of that, she appears very well trained. Good for you and good for her.
Jim, you appear to have made certain changes to your original posting which I believe has improved the image somewhat. The halo effect from over sharpening has gone and I wasn't too happy with the end of the bow obscuring her left eye. Much better now but still worry about the hair strand which appears to be sprouting from her nostril. Should be easy enough to clone out. Congratulations on a very fine image with great potential.
Of course, I am of the old school who thinks a shoulder pad only makes one struggle to produce a good violin sound, but in spite of that, she appears very well trained. 
Good for you and good for her.