From your list it's Floyd. I like slicksters or technicians. Think Whitaker, Hopkins, Floyd, Martinez, etc.
I wasnt born in the Tyson and Ali era, so I have to go with Floyd. He is the best fighter my eyes has ever seen.
Alexis Arguello Danny "Little Red" Lopez Tommy Hearns Mohamed Ali Marvin Haglar Micheal Spinks Larry Holmes Bobby Chacon George Foreman Joe Frazier Honorable Mention: Jerry Quarry Murray Sutherland George Chuvalo My home boy Denny Moyer Winky Wright Bronco McKart Miguel Cotto Kelly Pavlik Antonio Margarito Glen Johnson And a couple dozen other guys