Not completely rehabilitated, by any means (nor can he ever be, I think), but Reinhard Heydrich’s record as Reichsprotektor of Bohemia has been reevaluated a bit in recent years. He knew the Germans needed the Czechs’ industrial machine humming along smoothly during WW2, so he raised wages, opened resorts to Czech workers, gave them more vacation time, etc. He at least gave lip service to the puppet Czech government and actually tried to win over the Czech people to the German cause, not entirely through police-state tactics.
Still the same evil Nazi who chaired the Wannsee Conference, though.
We have a very different opinion of black leaders (such as leaders of slave revolts) nowadays than most people did in 1860.
There is a plaque honoring Toussaint L’Ouverture in the Pantheon in Paris now, and there is at least some support for the idea that his remains should be moved there. I’m sure that’s not how the French of the early 1800s would have thought of him.
Native Americans in general get better press now than they once did.
Witches are portrayed more positively now than they once were, at least in the mainstream in Europe and the non-fundamentalist mainstream in America. So are members of other non-Christian religions.
This isn’t quite what the OP had in mind, but George Wallace, of “segregation now, segregation tomorrow, segregation forever” fame, eventually had a change of heart and apologized for his earlier ideas and actions.
Johannes Kepler predicted that Mars would have two moons. This was discovered years later to be correct, but his reasoning was totally wrong- he thought that, since Earth has one moon and Jupiter was thought to have four at the time, the planet in between should have two. There is such a thing as a coincidence, after all.
I’m not very familiar with the Tower of London (I’ve only been there once, on the tour), but how many reasonable places are there in the Tower to bury bodies in secret? If there aren’t many, it gets a lot easier to make a good guess. Also, how specific is More’s prediction? If it’s something vague, something on the order of the stereotypical psychic’s prediction, then it could easily be counted as a true prediction even if it isn’t- the same thing happens with psychics’ predictions today.
Gen. Benjamin “Beast” Butler took a lot of postbellum heat from Southern historians for his actions as military governor of New Orleans during the Civil War, but is generally credited today for enforcing law and order, reducing disease, improving sanitation standards and protecting the previously-oppressed black population.