The scorecards seldom told the whole story of the first 5-7 rounds in an Ali fight, since he was happy to give away a couple of early rounds just feeling his opponent out. The scorecards was probably quite close when he KO'd Folley for example, but that doesn't mean it was a close fight. With the exception of round 5 Ali controlled just about the whole fight against Liston. He clearly had the upper hand. And that version of Ali wasn't quite as good as the one who beat Williams, Terrell and Folley. Dundee said Ali still was improving, that he was becoming stronger without losing his speed, when he was forced into exile.
On Baker-Layne bouts-I don't think they were controversial, but were apparently conpetitive enough to warrent three fights. Layne was going back by this time and had begun to lose frequently. I think the Layne of 1950-51 was a much tougher kettle of fish. That is a problem with making a list such as you did. Some fighters reach a higher level but fade fast. Others maintain themselves a long time. Layne and Firpo are the first type. Savold, Cooper, and Chuvalo the second. It is a personal choice, but in rating them I would focus heavily on beating the best men available at their best. Layne beat two champions at least near their prime. Firpo one, who was old. Savold, Cooper, and Chuvalo never beat a champion. I agree that Layne could hit, but Firpo had extraordinary power. It was his one big asset, besides size and durability, and carried him very close to the championship. I think had the 1951 Layne fought the 1923 Firpo, Layne wins. One problem with comparing them is that Layne fought far tougher competition and thus his stats will never be as impressive. Firpo fought quite a few second raters, even when a contender.
I expected you would Janitor.Gains wins over Schmeling by ko. Godfrey,Renault,Gorman,Jones,Spalla ,and Charles plus his victory over Carnera ,in which he dropped the big guy ,give him the nod ,imo,also there was no hint of fix attached to any of his wins.