Depends what rating he's being given. I don't think many people have him in their all-time heavyweight top 10 or 20. He had lethal power and a good chin, a dangerous combination for anyone to face, but could be neutralised. He still did pretty well, bearing in mind he was a short, squat guy in an era of superheavyweights. He also wasn't very well managed and seemed to struggle to get big fights. He still KO'd four past or future heavyweight champs, not many can say that.
No, He would not, in fact Tua would have a good chance to knock him out, Louis was small,static with poor chin
I see two murderous punchers who were quite limited otherwise. Baer beat and knocked out better fighters though and his power is amazing by eye test. So again, based on what?