An interesting 'accordion' dress concept I saw on a Chinese dress site people might be interested in (link to dress in comments) : sewing. It would be interesting to not too a bunch of colors for the accordion part, but just one.
Gorgeous gray bridesmaid dress with silver sequin sleeves. A-Line/Princess V-neck Asymmetrical Tulle Evening Dress With Ruffle Beading Sequins. On Sale, in many colours and all sizes, customisable too!