I think the Ali right prior to exile would have got around this with his extra speed, stamina and movement. Norton always would have been tough but i see a young Ali winning decisions.
He dropped Bonavena and Mildenberger with hooks, and hurt Liston with a hook in the first fight. By contrast, I don't know of too many times that he was able to have the same effect on his opponent with an uppercut-and given the height advantage he had over opponents, you'd think that would be a punch he would have had in his tool kit. Robinson sometimes seemed to have problems with movers and counter-punchers. Servo ran him close. So did a past prime Abrams. His defense wasn't as good as his offence, either. Granted, his offense was amazing, but he could be tagged in return.
Ali's biggest weakness in the long run was that he wanted to fight like Sugar Ray Robinson. He was briefly trained by the great Archie Moore who wanted to teach him longevity. Slipping and punching, knocking guys out, while taking little in return. Ali, who was Cassius Clay back then, didn't want to box like Moore who held the most knockout wins in history, he wanted to box with a sweet style like SRR. You could argue in the long run this had the most effect on Ali's health. He lost the best part of his reflexes after his exile, and he never had the proper fundamentals which resulted in him taking more punishment in the 70s. It made for arguably the most exciting career in boxing history though.
I sometimes think SRR traded a bit too often and neglected his boxing skills. This goes somewhat hand in hand with the defense comments.