Your top 3 comedians

Red Skelton
George Burns and Gracie Allen
Carol Burnett

Red because for all his comedy he never denigrated anyone or anything and his pantimime was superb
George and Gracie were a rare team that were similiar enough to people you might actually meet, unlike say lucy and desi.
Carol Burnett was sort of the follow up to Red Skelton in more modern times both good and gracious, nice qualities while making one laugh

Bill Hicks
Richard Pryor
Dennis Leary

Jon Stewart
Bill Maher
George W. Bush

Jim Norton
Bill Burr
Not Rich Vos

I assume, based upon your list, that you are asking for standup comedians, rather than groups of comedians.

In no particular order:

Bill Cosby (mostly for his standup work, although some of his TV work was good too.)

Bob Newhart (Again, mostly for his standup work, but again, his TV work was good too.)

Jerry Seinfeld (This time mostly for this TV work, but his standup was good too!)

If you were allowing comedy groups, my list would have:
The Marx Brothers
Monty Python Flying Circussssss
The Three Stooges

My three cents worth