Ok. Mind you, I have NO clue as to what I am talking about.

For evening wear, I could see a tweed kilt and coat look being pulled off with brown leathers. Shoes, belt, sporran, straps, etc. Probably the hardware on the kilt in brass with leather. The tweed of course should be brown with little hints of darker colours, like greens or even dark burnt oranges.

Some people of course could pull this look off better than others... I think it would look dashing.