Am I the only one on this forum that doesn't rate Keita to be the successor of anyone? He will be pushed out when/if Jonathan blossoms and/or the arrival of fabregas.
He's 29, of course he's not anyones successor. He's just a very, very useful and excellent squad player. Great mentality and he adds something different to the team.
I think for him to truly excel we need iniesta at LW and busquets at DM. they add the creativity which means keita can get on with his job of being an epic goal threat.