http://www.blacktieguide.com/Classic...ents/Waist.htm
OP hasn't mentioned shoes yet. The most formal is supposedly the opera pump. But I think a lot of men have issues with wearing a shoe that has a giant bow on it. Thus, most men choose the patent leather plain toe oxford. I say go for the pump, though.
http://www.blacktieguide.com/Classic...s/Footwear.htm