the pose and perspective is very good in my opinion, however I am not so sure about the BW conversion, you seemed to choose the red channel particulary, which give an artificial adnd light, soft look. It may be what you like, but you might try the green channel a bit more.
Hmmm, I am not a color specialist, but the white balance seems quite a bit off in my opinion. Also its a bit bright, not easy to do a b&w conversion because there are little contrasts. maybe your first conversion was the best way to do it, as a high key portrait
I just happened to see this when I popped into this forum.
Your pose of the subject is very nice but the frame composition has the subject's face on the left side with too much shoulder and background on the right. I would prefer more plain background to the left of her face and hands as a lead-in to her face.
You might try cropping this shot by cropping out from before the ear on the right because the shoulder dominates that portion of the picture with that big earring jumping out. It almost looks like a product shot for the earring.
She is a beautiful model and your soft focus high-key treatment looks nice.
I like the soft look, and even the B&W conversion, but this shot doesn't say "portrait" to me. She looks distracted, like she's fiddling around with an earing, or about to examine her nails. To me there is no center of interest, really nothing to look at.