I think Stones is probably our most complete centre back in terms of positioning, tackling, passing, ball-carrying, aerial ability, and since 2020 or thereabouts he's ironed out a lot of the errors in his game (not to say he'll never make any mistakes, no-one's perfect, but they happen less than they used to and when they do happen they don't seem to destroy him mentally like they used to). His injury troubles are a crying shame because I think he's only consistent fitness and a good run of form away from being absolutely everything you could want in a centre-back. Needs to be very carefully managed and wrapped in cotton wool in order to be available for every match we want him in. What I really like about him over the past couple of years is his ability to effectively mark a top striker out of a game. He has the skill and concentration to stick to that task for a full match and restrict that striker to feeding on scraps. I don't think any of our other defenders do that job anywhere near as well.
I see Laporte as quite similar to Stones, almost like the left-sided version of him. I might rate his passing a little higher than Stones's, and Stones's dribbling a little higher than Laporte's, but it's fine margins. Both very good players who play a similar role. I think Laporte is slightly more error-prone, and slightly more likely to let those errors get to him and turn one mistake into a poor match.
Dias is not quite so good as the other two in terms of bringing the ball forward from the back (although he's still good at this) but he adds a controlled aggression that neither of the other two has much of, and also the vocal leadership and organisation, which is vital especially in tough matches. Goes to ground just a little too easily in the tackle for my liking. But strong, powerful, puts his body on the line.
I don't think Aké's quite as good as the other three. He doesn't have much by way of obvious weaknesses but equally doesn't quite hit the same highs in the strengths. Despite his height I think he's very good in the air, his height would only be a concern if we were up against a striker that was both excessively tall and a strong header of the ball. Against a decent header of 6'2", say, I'd back Aké to defend as well as anyone.
Everyone being fit, Stones/Dias is my preferred CB partnership. It seems the best match of both skillsets and personalities - when they went on that run playing together in 20/21 it was obvious they knew their roles well and could rely on each other on the pitch and that translated to some fantastic performances.
But there's no duo of the four that would give me major cause for concern in most matches. If I was Pep I'd rotate heavily, not just to balance fitness concerns and game time requirements but because different opponents are sometimes best dealt with through slightly different defensive approaches, and each player is more suited to some approaches than others.
