I actually think standing out from the industrial crowd in your romantic velvet would be delightful! However, if you want to change it up a bit, I totally understand that.
Well, since I'm also a plus-size, I know what a dilemma it is to find a suitable outfit. I think Alenuska's idea of the cheongsam and boots is cool, but if you're anything like me, you would NEVER leave the house with a second-skin PVC/silk dress on. We curvy gals often need some help in the waist covering department.
So, my idea would be a big, poufy short skirt like this (but with a crinoline under to make it bigger), black fencenets with purple tights underneath, an underbust corset and maybe a silk top with a mandarin collar or some other top with a high collar and no sleeves. Don't forget the stompy boots!