I make mine very simple and they seem to sell well at the boutique that I'm selling. Too well, since I have a full time job and crafting is just part-time fun for me and I don't always have time to make something upon request. Anyway, I glue 18" strips of tulle to the backside of the large bodice that I freehand drew and 12" to the back of the small. I tend to use about 40 strips on the large ones and about 30 on the small. Some of mine come out better than others. When I make it because I want to, it always comes out way better than when someone dictates how they want me to make it.
Here's a link to a slide show of 4 that I recently made. http://leeleebeau.com/LeeLeeBeaus_Boutique.php
Sorry about the website, my husband stole the LeeLeeBeau name to start a horse trailer business and I just stuck my page on his site to let family and friends see what I'm up to. I don't sell online so this works for me...
Oh, I also use foam core, batting under the fabric and finish off the back with felt.