I think it's a damn shame if Ncuti Gatwa isn't given the chance to play the Doctor for three seasons, but it will be even worse if Billie is just a stand-in for someone else to play the Doctor. If you're going down this road, have the balls to play it out!

And if you do go down this road, what I think you need to do is bring Rose back to show definitively that the 16th Doctor ISN'T Rose. Ironically this will come by showing how much the real Rose has changed, while 16 is a reflection of the Doctor's memories of that relationship. I can easily believe the Doctor has that obsession since it's a reflection of the showrunner's.

Nostalgia will only get you so far. Billie has to show that her Doctor is her own woman. Make us want to see new adventures with THIS Doctor than merely ing when she was with 9 and 10.

Ireland was already Christian in the 1200's, but if he lived in the 1200's, that would have be around the time Henry II and the English were conquering Ireland. (In a huge piece of irony, Henry II was personified for moviegoers in two big Hollywood movies by an Irish actor's Peter O'Toole.)

I really don't think Disney is going to recreate the Sue-Namor-Reed love triangle. Maybe Scott-Jean-Logan, but I think Sue's wedding ring will make the Namor subplot off-limits.