For me it's Peter Davison, exasperated, wise, and so English.
or Tom Baker, funny, shouting, google eyed. Like a mentally unwell uncle, allowed out on a Saturday evening.
The last two were pretty good. But they've had to much money, and effects to work with.
In the days of proper Dr Who, you had a cold Welsh hillside, a man in a green chicken suit, and 10 episodes of meaningless techno babble.
That's the test of a real actor.
Apart from when it was filmed in Provence, then it's get it filmed as fast as you can so you can get down the local bar.