So anything that has "Lula" as the name I pretty much become a 100% fan.
While at the spa yesterday (yes I want to rub that in). I was looking through a bridal magazine and saw LulaKateBridal. They have clean, crisp bridesmaid's dresses in a TON of colors. The lines are simple (but isn't that what you want?). The dresses on the website are mostly silk and taffeta, but they do have other fabrics and colors available on request ~ in case you want things really Matchy/Matchy.