The Lady is no Iron Lady.
Yes, Aung San Suu Kyi (the subject of The Lady) is, historically speaking, a much better person than Margaret Thatcher. But the film about the current leader of Burma's main opposition party is nowhere near as good as the film about the former prime minister of the United Kingdom.
Yes, Michelle Yeoh (who plays Aung San Suu Kyi) gives her role everything she's got, but the script is not good, the cinematography is flat, the soundtrack is wack, and the director (Luc Besson) seems to have slept during the entire production of the film.
Yes, Aung San Suu Kyi is a world-historical figure, but she may not be the best subject for a film. A decent and principled person with a beauty that is spiritual, Suu Kyi is a living symbol of calm and concern. She is not mad. Thatcher was and still is mad, and mad people are much more entertaining than nice and calm people.
One other thing: A biopic about a famous politician should always be about a moment in that politician's career—the moment before rising to power, the moment while in power, the moment before falling from power, the moment after the fall, and so on. The film should not be about the politician's whole life. Yes, a book (as a storytelling technology) can handle the whole life of its subject; a film (in two hours) just can't.
Luc Besson should stick to action films.