No Dempsey, Jack Johnson, Willie Pep, Joe Louis, John L Sullivan, De La Hoya, Pac, SRL, Hagler, Hearns, Duran or Marciano? There's countless others I've missed but I'm not sure how Liston, Tyson, Foreman, Frazier and even Floyd are there.
If we're talking influential IMO it's Dempsey (first $1million gate, first star), Joe Louis (His second fight with Schmeling was huge, especially given the timing in the rise of Nazi Germany), Jack Johnson (first black HW champ, one of the first to embrace the heel role) and Ali (Given his cultural standing more than his ability.) Tyson is a close fifth given his stupidly awesome rise but I'm bias as fuck there. Floyd given his PPV drawing ability could also be mentioned here.
If we're talking accomplishments : Ali (3 time HW champ), SRR (the most technically proficient fighter of any era),SRL (Olympic gold, countless World titles and reigned in arguably the greatest division ever) and WIllie Pep (Regarded as one of the GOAT FWs of all time and a P4P great) RJJ is probably worth a shout here also, in fact put him in above Pep for his cross divisional greatness.
If it's for what they could have achieved : Tyson (if he didn't leave Rooney he'd have gone down as the best ever, I honestly believe that, his boxing IQ could have adapted to any opponent it's cliché but still.), Foreman if he had the mental fortitude he did in his comeback during the 70s he rules the division with an iron fist, Prince Naseem (again I'm bias here but if he didn't get so large between fights so he could actually train he could have been even more special than he seemed to be) and I'm not sure who to put as the 4th.
All opinions and that though.