I believe Raina, Kaif or Gautam Gambhir may do a better job.
You cannot keep a player as he creates fear amongst bowler. What fear will he create when he cannot stand there for more than 1 - 2 overs judjing by recent performances.
TAKING CHANCES, is it the best approach for a tournament like world cup. NOT according to me. You should keep your best foot forward based on present best choices not on past performance or HOPES that a non-performer will suddenly perform.