I was just in Atlantic City last summer for a bachelorette party and I was looking at dresses, but actually wound up wearing a black romper (it might have actually been a swim suit cover up, lol) and I was so comfortable all night- and it was still pretty sexy.
I can't find the actual one I wore, but it looked something like this
And I wore it with high cuff booties, kind of like this
I threw on a statement necklace and was done! Super easy, flattering, and you can dance without worrying about your skirt riding up.