First off, you have a great start! I can really associate this with your character.
I'm guessing you want help making it look more complete/prof.?
I would make the highlights more defined by brightening them, and while I understand the concept of the abs and ****s showing through the fabric, your reference pic is fan art made by a um, excited dude. (If not then I'm thoroughly confused by the woman who drew the fan art, lol)
I would think a more fitting dress hem style would be a double slit, but a single works okay, only it looks more like a pant leg. If you want to keep the single slit hem I would suggest making the hemline ripple like this picture
The fishnet garter is a cute touch, I like the edginess it gives the doll.
I have almost no experience with curly hair, but yours is a fabulous first try. If you would like to touch it up, I think filling inbetween the strands would be a good idea, and to add variety in your shading. For example, all the curls have the highlights on top and the shaddows on the bottom, not only is that too uniform, but it's also a bit pillowy Try more of a candy cane effect, like this.
Except on the width parts of the curl do shading. If that doesn't make sense I'm sorry, but if I had a pixel example of how I'd do it I'd show you, but like I said, I've only got slim-to-none experience with curls.