My additions to your list:
Thought it'd be interesting to list any "weaknesses" these guys had (or supposedly had). Feel free to add, or tell me I'm wrong...
Jack Hobbs- played in a very batsman friendly era. [Not really, before WW1 he was the only one who averaged around 55, while no one else crossed 45]
Wally Hammond- []
George Headley- played against weakened sides.
Len Hutton
Garry Sobers- batted down the order [Not really, he batted even better at 3 & 4. The team preferred him at down the order]
Sunil Gavaskar- rated highly against the WIs, but it's perhaps a bit of a myth, as he didn't get extensively tested against the 4 quicks. [Agree]
Graeme Pollock- not many tests
Greg Chappell-
Barry Richards- lack of tests
Viv Richards-
Sachin Tendulkar-
Brian Lara- [In the middle of his career he had a horrible slump, in the middle of which he produced the greatest batting performance of modern times : ****ing magnificent enigma, Also struggled against extreme pace especially against two Ws, Donald]
Ricky Ponting- susceptible to quality spin [8 years of awesomeness surrounded by 4 years of mediocrity at start and at end of the career]
Jacques Kallis- [Great batsman, but it is telling that when the team is at their best as in 2008, or as in 2011 onwards : the key batsman were Smith (2008) and Amla, ABDV (2011 + ). ]
W.G. Grace- hard to judge early era [Best by a long distance during his time]