[Ignore the previous poll if you saw it; I wanted the poll to go for a week instead of a day]
Idea stolen from @sillylotrpolls:
Counting all media, and you may take as generous a definition of companion as you like. To specify what 'number of characters' means in this context, if one character has multiple names, (fr'instance Bruce Wayne/Batman) that character only counts once. Otoh, multiple different characters with the same title, (ex. Dick Grayson, Jason Todd, et. al.) might all be Robin, but they each count as separate characters.
I think it would mean a lot to Kate Stewart to meet the Doctor who ultimately started her father's UNIT journey. Because of Timey Wimey stuff she can't tell him who she is of course, but she can still show some thanks.
Bonus:
I like to imagine since Donna works for UNIT now, she likes to ask Kate along for lunch occasionally. And I also think 14 wouldn't hear the END of it once she finds out about Jamie.
in the second to last serial of classic doctor who, the curse of fenric, there are strange pseudo vampires. at one point the doctor explains that - despite the folklore - it’s not the physical crucifix that repels the vampires, it’s the faith of the person holding it, their absolute belief in something more than themselves. the priest present fails to repel the vampires with a crucifix, because his faith had been broken by the events of WWII. the doctor repels the vampires with his faith in those he has had as companions, muttering their names over and over.
i mention all this because - and i am not making this up - it is immediately followed by a soviet man repelling the vampires with the power of belief in communist revolution. they aired this in the 80s.
as the show was then cancelled one story later, it remains the only show to ever be cut down in its prime twenty six seasons in.