Composition: I like the profile shot. Her positioning in the frame is really good. I like that she is looking into the photo.
Lighting/Exposure: Both are very nice.
Pose: Not too fond of the hand. It looks strange because of the wrist crop.
Suggestions for Improvements: If you get a chance to reshoot this, I will suggest the following: Have her bring her hand all the way up to her shoulder. Have her drop her shoulder and sit up very straight with her head high. It will provide a visual difference or gap between her head and torso and it will prevent cropping at any joints.
This is a lovely portrait overall. You did a fine job with that exposure. I always have trouble getting my focus just right in low light situations. Nicely done! :)
I love this style of lighting. Have you converted this to B&W for effect? Rim-light tends to lend itself well to B&W as it's all about shape.
of course I did :). But I liked the color version better. What I like is that it is almost B&W but not quite, the color is very minimal but it adds warmth to the portrait.