Perhaps not the heaviest handed. But Ali could punch. Yes, Ali was well rounded but he primarily outboxed -people using his speed. Look at Ali's left hook on the rugged and durable Oscar Bonavena. Or the right hand that hurt Ron Lyle leading to a flurry that tko'd Lyle. Even more impressive, look at the combinations Ali landed in round 1 of the Liston fight. The iron jawed Liston was absolutely stunned at what was hitting him. Ali also nailed Foreman with hard lead rights that stunned him and he backed up Foreman in both rounds 3 and 5 before George got tired. Mayweather is a great pick at lighter weights.
Pea gets overlooked. He went to the body pretty good. Starched unbeaten Loumeli in two. Iced Nazzario in one. Dropped iron chinned Haugen.