I enjoy the irony of referring to Kallis as a perfect cricketer as a defence against him being labelled overrated.
Didn't say best, didn't even say perfect batsman, because he wasn't.
But he played the perfect role.
And if you thought up the the most valuable combination of skills, matched with production and value of position for a top order batsman, it's him.
Seriously, he batted primarily at 3 or 4, averaging over 60 at no. 4, was a top 3 2nd slip fielder during his era, and quite frankly for the time I've been watching cricket, and finally as a bowler consistently came on at either 1st or 2nd change, being easily the 2nd best batting all rounder ever.
What possibly more could he have done?
Yes, Sachin was the better batsman, Garry the better cricketer (in all 3 facets), but the roles Kallis played, in the positions he performed and the balance they achieved with him (where the WI failed with Garry), beings me to that point.