His hair is almost white again, but there’s much more of it. He appears younger than his first incarnation, but older than his second, and looks more… distinguished, perhaps. He’s certainly gained a more authoritative demeanour.
The clothes he chooses to reflect his new persona are flamboyant; velvet jackets, frills and lace-trimmed cuffs to his shirts, even a cape. He’s a man of style and elegance, the kind of person even UNIT’s bigwigs can’t help but listen to, at least some of the time. Just as well since he’s currently stuck on earth. Hopefully he can do some good here.