Think i need to agree with those thinking Pep needs to stop playing him at CB. It's obviously not a position he can play for the same reason we don't stick him up on the wings or up front, he doesn't have the skill set to compete there. The only people who should be playing CB are:
Puyol, Pique, Abidal, Mascherano and members of the B team.
Busquets has also shown he isn't strong in the air, which is why i think instead of placing him in the centre of the box on set pieces he may be better suited to being the man closest to the ball when our opponents are taking corners. He would then hopefully be tall enough to deal with any poor or low corners that are knocked into our area that don't clear the first man.