I think you have a really great start. Just a few things (which you can take or leave):
The pearl necklace is a great idea, but it is really hard to see. You should add some shadows underneath it on the skin so it stands out more.
I like the idea of the belt, but you might try a different shape. The one you have looks a bit tubey. Maybe something more square, or you could look up fashion belts on google to get some inspiration.
For the shoe. You might try just doing a simple front view of a pump. Here is the way that would look. It's much easier than side or 3/4 view. All you have to do is draw the shape and add/delete pixels as needed on the foot.
Also I agree with Bridie about shading under the hair and skin. For the bracelet you might actually ask Ness if the background of the finished image is going to be dark or light before you change it.
Well those are my thoughts.