Jodie Whittaker is leaving Doctor Who. Two of the potential replacements are Kris Marshall and Michael Sheen. The others I haven't heard of. I can't really comment on them. I've enjoyed Michael Sheen in everything I've seen him in. I haven't seen Kris Marshall in as much. The first thing was Death in Paradise. I think I could be happy with either one.
Should be Sean Pertwee... Although there is high chance he’d decline (or costs way too much to hire), but I still think the son of the best Dr. should be the Dr.
Sure Cushing would have been great as the Dr., but alas, no such luck. And C.Baker was an order of magnitude better than Davison. Davison is the last on the list, that much is certain...