Very interesting question, almost impossible to get right, I know I will forget a couple of deserving fighters, but I will try:
Sugar Ray Robinson
Muhammad Ali
Joe Louis
Henry Armstrong
Rocky Marciano
Jack Johnson
Jack Dempsey
Julio Cesar Chavez
Roberto Duran
Harry Greb
Sam Langford
Marvin Hagler
George Foreman
Ricardo Lopez
Khasiao Galaxy
Thomas Hearns
Sugar Ray Leonard
Willie Pep
Manny Pacquiao
Archie Moore
Honorable Mentions:
Sandy Saddler
Young Stribling
Aaron Pryor
Salvador Sanchez
Roy Jones Jr.
Bernard Hopkins
Sonny Liston
Joe Frazier
Charlie Burley
Carlos Monzon
Wilfredo Gomez
Hector Camacho Sr.
Carlos Zarate
Izzard Charles
Gene Tunny
Tony Zale
James Toney
Rocky Graziano
Jake LaMotta
Evander Holyfield
1. Muhammad Ali
2. Sugar Ray Robinson
3. Joe Louis
4. Henry Armstrong
5. Willie Pep
6. Roberto Duran
7. Sugar Ray Leonard
8. Benny Leonard
9. Sam Langford
10. Rocky Marciano
11. Ezzard Charles
12. Harry Greb
13. Jack Johnson
14. Carlos Monzon
15. Marvin Hagler
16. Jack Dempsey
17. George Foreman
18. Julio Cesar Chavez
19. Larry Holmes
20. Manny Pacquiao
1. Sugar Ray Robinson
2. Henry Armstrong
3. Roberto Duran
4.Willie Pep
5. Emile Griffith
6.Harry Greb
7.Julio Cesar Chavez
8 Sugar Ray Leonard
9. Alexis Arguello
10.Muhammad Ali
11.Joe Louis
12.Rocky Marciano
13.Jack Johnson
14. Wilfredo Gomez
15.Archie Moore
16.George Foreman
17.Marvin Hagler
18.Jack Dempsey
19.Carlos Monzon
20.Thomas Hearns
I give the edge to the lighter weight fighters mainly because they bring a combination of talent ability and much more to the table than the heavyweights. If this was a list of historical impact men like Muhammad Ali Jack Johnson and Joe Louis would be at the top of the list.
1. Sugar Ray Robinson
2. Muhammed ali
3. Julio cesar Chavez sr
4. Henry Armstrong
5. Joe louis
6. Willie pep
7. Roberto Duran
8. Jack Johnson
9. Sugar ray leonard
10. Sam langford
11. Rocky Marciano
12. Bernard Hopkins (career still ongoing, oldest champion in boxing history, great resume, isnt finished yet)
13. Archie Moore
14. Jimmy wilde
15. George Foreman
16. Floyd Mayweather (career still ongoing, 8 time world champion in 5 divisions, good resume)
17. Manny pacquiao (career still ongoing, good resume, started as a flyweight and dominated welterweights)
18. Jake lamotta (good resume, gave sugar ray robinson first defeat, had 5 epic fights with sugar ray robinson)
19. Juan manuel marquez
20. Salvador sanchez
1.Sugar Ray Robinson
2.Muhammed Ali
3.Harry Greb
4.Henry Armstrong
5.Willie Pep
6.Joe Louis
7.Roberto Duran
8.Jimmy Wilde
9.Archie Moore
10.Benny Leonard
11.Marvin Hagler
12.Sam Langford
13.Joe Gans
14.Sugar Ray Leonard
15.Carlos Monzon
16.Stanley Ketchel
17.Sandy Sadler
18.Larry Holmes
19.Kid Gavillan
20.Sonny Liston
give 10 points
