For sure, important questions. For some famous people, I think, there is hardly any redeeming quality. Would you agree that Germans would be foolish to celebrate Hitler’s birthday as a national holiday? OK, I understand he did like animals but I doubt PETA would think of him as a treasure because of that. Same with Stalin?
Napoleon is mixed. Certain civil liberties, for Jews for example, were achieved under his reign (the Napoleonic Code), but yes, he was an imperialist. Who does make that determination? The government of France, I suppose.
In the United States, it is more complicated, because there has always been a tension between the power of the central (federal) government and States’ rights. So should Alabama alone make the determination regarding a state holiday for clearly confederate leaders such as Jefferson Davis and Robert E. Lee? I think not, because it really is a slap in the face to what we, as a nation, stand for and what we are still trying to achieve: that is, liberty and equality for all. But I think your point is an important one, nonetheless.