Lack of pace is not the thing, lack of agility when skilled players run at him and force him to turn. It is physics, he is a big lad, even by CB standards. Might be quick in a straight line, but straight line races are a small part of a defenders game.
Good footballer, strong in the air, but would have concerns over his defensive ability against top end players. He made quite a few mistakes during the season, but because he plays for Leicester they get forgotten very quickly. Will not happen when he gets his big move.