I decided to make a list based on records, level of competition and postseason success. I used this to help with my own opinion.

MY OPINION

1. 1927 NEW YORK YANKEES

2. 1939 NEW YORK YANKEES

3. 1998 NEW YORK YANKEES

4. 2018 BOSTON RED SOX

5. 1932 NEW YORK YANKEES

6. 1961 NEW YORK YANKEES

7. 1975 CINCINNATI REDS

8. 1912 BOSTON RED SOX

9. 1942 ST. LOUIS CARDINALS

10. 1944 ST. LOUIS CARDINALS

11. 1937 NEW YORK YANKEES

12. 1936 NEW YORK YANKEES

13. 1907 CHICAGO CUBS

14. 1905 NEW YORK GIANTS

15. 1970 BALTIMORE ORIOLES

16. 1995 ATLANTA BRAVES

17. 1999 NEW YORK YANKEES

18. 1929 PHILADELPHIA ATHLETICS

19. 2016 CHICAGO CUBS

20. 2009 NEW YORK YANKEES

TOP 20 BASED ON W-L RECORD

1. 1906 CHICAGO CUBS 116-36

2. 2001 SEATTLE MARINERS 116-46

3. 1998 NEW YORK YANKEES 114-48

4. 1954 CLEVELAND INDIANS 111-43

5. 1909 PITTSBURGH PIRATES 110-42

6. 1927 NEW YORK YANKEES 110-44

7. 1961 NEW YORK YANKEES 109-53

7. 1969 BALTIMORE ORIOLES 109-53

9. 2018 BOSTON RED SOX 108-54

9. 1975 CINCINNATI REDS 108-54

9. 1970 BALTIMORE ORIOLES 108-54

9. 1986 NEW YORK METS 108-54

13. 1931 PHILADELPHIA ATHLETICS 107-45

13. 1907 CHICAGO CUBS 107-45

15. 1932 NEW YORK YANKEES 107-47

16. 2019 HOUSTON ASTROS 107-55

17. 1939 NEW YORK YANKEES 106-45

18. 1904 NEW YORK GIANTS 106-47

19. 1942 ST. LOUIS CARDINALS 106-48

20. 1998 ATLANTA BRAVES 106-56

20. 2019 LOS ANGELES DODGERS 106-56

TOP 20 BASED ON PYTHAGOREAN W-L RECORD

1. 1906 CHICAGO CUBS 115-37

2. 1939 NEW YORK YANKEES 111-40

3. 1969 BALTIMORE ORIOLES 110-62

4. 1909 CHICAGO CUBS 109-44

5. 1927 NEW YORK YANKEES 109-45

6. 2001 SEATTLE MARINERS 109-53

7. 1998 NEW YORK YANKEES 108-54

7. 2017 CLEVELAND INDIANS 108-54

9. 1942 NEW YORK YANKEES 107-47

9. 1942 ST. LOUIS CARDINALS 107-47

9. 1944 ST. LOUIS CARDINALS 107-47

12. 2016 CHICAGO CUBS 107-54

13. 1975 CINCINNATI REDS 107-55

13. 2019 LOS ANGELES DODGERS 107-55

13. 2019 HOUSTON ASTROS 107-55

16. 1904 NEW YORK GIANTS 106-47

17. 1998 ATLANTA BRAVES 106-56

17. 1998 HOUSTON ASTROS 106-56

17. 1974 LOS ANGELES DODGERS 106-56

20. 1909 PITTSBURGH PIRATES 105-47

TOP 20 BASED ON WP%

1. 1880 CHICAGO CUBS .798

2. 1876 CHICAGO CUBS .788

3. 1885 CHICAGO CUBS .777

4. 1906 CHICAGO CUBS .763

5. 1885 NEW YORK GIANTS .759

6. 1884 PROVIDENCE GRAYS .750

7. 1902 PITTSBURGH PIRATES .741

8. 1886 CHICAGO CUBS .726

9. 1909 PITTSBURGH PIRATES .724

10. 2001 SEATTLE MARINERS .716

11. 1927 NEW YORK YANKEES .714

12. 1886 DETROIT WOLVERINES .707

13. 1897 BOSTON BRAVES .705

14. 1998 NEW YORK YANKEES .704

14. 1931 PHILADELPHIA ATHLETICS .704

14. 1907 CHICAGO CUBS .704

17. 1939 NEW YORK YANKEES .702

17. 1879 PROVIDENCE GRAYS .702

19. 1877 BOSTON BRAVES .700

20. 1896 BALTIMORE ORIOLES .698

TOP 20 BASED ON RUN DIFFERENTIAL

1. 1939 NEW YORK YANKEES +411

2. 1927 NEW YORK YANKEES +376

3. 1876 CHICAGO CUBS +367

4. 1885 CHICAGO CUBS +364

5. 1895 BALTIMORE ORIOLES +363

6. 1897 BOSTON BRAVES +360

7. 1894 BALTIMORE ORIOLES +352

8. 1886 CHICAGO CUBS +345

9. 1902 PITTSBURGH PIRATES +335

10. 1936 NEW YORK YANKEES +334

11. 1896 BALTIMORE ORIOLES +333

12. 1906 CHICAGO CUBS +323

13. 1885 NEW YORK GIANTS +321

14. 1898 BALTIMORE ORIOLES +310

15. 1998 NEW YORK YANKEES +309

16. 1937 NEW YORK YANKEES +308

17. 2001 SEATTLE MARINERS +300

18. 1942 NEW YORK YANKEES +294

19. 1886 DETROIT WOLVERINES +291

20. 1897 BALTIMORE ORIOLES +290

TOP 48 IN THE POSTSEASON BASED ON RUN DIFFERENTIAL

1. 2007 BOSTON RED SOX +53

2. 1996 ATLANTA BRAVES +39

3. 2018 BOSTON RED SOX +33

3. 2005 CHICAGO WHITE SOX +33

4. 1970 BALTIMORE ORIOLES +30

5. 1998 NEW YORK YANKEES +28

5. 2009 NEW YORK YANKEES +28

5. 1960 NEW YORK YANKEES +28

5. 2013 BOSTON RED SOX +28

5. 2001 ARIZONA DIAMONDBACKS +28

10. 1999 NEW YORK YANKEES +27

11. 1995 ATLANTA BRAVES +26

12. 1983 BALTIMORE ORIOLES +25

13. 2015 KANSAS CITY ROYALS +24

14. 2011 ST. LOUIS CARDINALS +23

14. 1987 MINNESOTA TWINS +23

14. 1989 OAKLAND ATHLETICS +23

17. 1976 CINCINNATI REDS +22

18. 2004 BOSTON RED SOX +21

19. 1936 NEW YORK YANKEES +20

19. 2008 PHILADELPHIA PHILLIES +20

19. 1910 PHILADELPHIA ATHLETICS +20

19. 2006 ST. LOUIS CARDINALS +20

19. 2002 ANAHEIM ANGELS +20

24. 1990 CINCINNATI REDS +19

24. 2014 SAN FRANCISCO GIANTS +19

26. 1932 NEW YORK YANKEES +18

26. 2016 CHICAGO CUBS +18

26. 2010 SAN FRANCISCO GIANTS +18

26. 1984 DETROIT TIGERS +18

26. 1982 ST. LOUIS CARDINALS +18

26. 1969 NEW YORK METS +18

32. 1928 NEW YORK YANKEES +17

32. 1981 LOS ANGELES DODGERS +17

34. 1937 NEW YORK YANKEES +16

34. 1979 PITTSBURGH PIRATES +16

34. 1985 KANSAS CITY ROYALS +16

37. 1978 NEW YORK YANKEES +15

37. 2003 NEW YORK YANKEES +15

37. 1919 CINCINNATI REDS +15

40. 1961 NEW YORK YANKEES +14

40. 1911 PHILADELPHIA ATHLETICS +14

40. 1988 LOS ANGELES DODGERS +14

43. 1927 NEW YORK YANKEES +13

43. 1923 NEW YORK YANKEES +13

43. 1938 NEW YORK YANKEES +13

43. 1907 CHICAGO CUBS +13

43. 1920 CLEVELAND INDIANS +13

48. 1939 NEW YORK YANKEES +12

48. 2000 NEW YORK YANKEES +12

48. 1954 NEW YORK GIANTS +12

48. 1905 NEW YORK GIANTS +12

48. 1993 TORONTO BLUE JAYS +12