You forgot about Kallis.Duminy was also pretty decent /most/ of the matches. Just need a bit of batting beyond him.
The problem in the top five is Smith.
Problem is, you can't put an out of form player in there match after match and hope he gets back into form somehow, especially in a world cup where country is supposed to play the top 11 in form players of their country, dunno if the selectors will ever learn that lesson....