Both of Eleven's main outfits have been eccentric, but primarily so because they're on a younger body. Well, and the current one is eccentric anyway, except that he adopted it in the Victorian era.
Anyhoo, I don't
want to see Twelve in anything remotely 9-ish or 10-ish. I'd rather see them go in a direction like 8, 2 or (maybe) 4 with his wardrobe. But as long as we stay away from Six's technicolor dreamcoat, I think we'll be okay.