My criteria would be heavily weighted in an artist that was the best at what he did at the time he did it...
Barks...would definitely be towards the top of the list.
Frazetta...not enough comic book work
Eisner...innovative but bland
Cole...not the best in any genre...good overall
Crandall...very good...does not separate himself from his peers...Craig, Feldstein, Davis, etc
Kurtzman...amazing but not even the best artist iamong his peer...that goes to Wood imho
Wood...makes for a strong argument with his body of work
Wolverton...too stylized for the general masses
Kirby...too attached to Simon...better with age
Schomburg...my #2
Fine...on mount rushmore
Everett...I believe he was the master of all trades