They're all brilliant in their own ways and I can't possibly rank them.
Otamendi is a fantastic defender. He's incredible at winning tackles, winning headers, making interceptions and all out aggression. All the more impressive considering his size! His ability to defend so high up the pitch was a key component in our ability to push teams back over the last two years. It disappoints me to no end when people continually talk of him like an accident waiting to happen when I'd wager he's made the fewest errors leading to goals out of any of our defenders (a bit like Mendy in that sense). Some people also only talk about him like a walking fouling machine whilst ignoring the fact that he makes tonnes of key tackles no other defender would. It's all part of his high risk, high reward style. I concede he does sometimes get that rush of blood to his head, but the pros far outweigh the cons here. He's probably the weakest of our CBs with the ball at his feet, but he certainly doesn't lack the confidence to bring the ball forwards. He's probably not the guy to take us to the next level due to his relative lack of ball-playing skills unfortunately.
Kompany on form is a colossus. He's aerially impeccable, incredible at making key blocks and clearances and certainly knows how to tackle. He actually scores goals with his head too! His leadership can never be understated. His dogged determination and bravery has led to so much good fortune for himself and the team on all levels. We're probably never going to see him at his true best due to his injury issues but it's a testament to his ability that he can continuously come back and play at the level he does. Ok, that does mean he's occasionally lacking in sharpness but 99% of the time it doesn't matter. He's around Otamendi's level with the ball; a better passer for sure (possibly our best on a technical level) but a bit weaker bringing the ball forwards (or at least riskier in style).
Stones is a weird one, in that he's the most erratic. On song he's defensively brilliant. He reads the game impeccably; his positioning can be a delight. He's assertive in the tackle, strong in the air and has brilliant timing with great leadership to boot. He's 100% our most important defender in a sense of building attacks. He's probably the weakest of all our CBs (Mangala aside) at actually carrying the ball and spraying it long distances. But he's the one and only CB on the planet who can read the midfield game so well and break the other team's front lines with passes into our midfield. I remember at the World Cup being so impressed with how consistently he got the ball pass the press into our midfield of Lingard and Alli. For me his inexperience is still a bit of an issue though, and sometimes if he's not at his best he can cause a few nerves. He can be critically error prone and a bit weak. Fortunately, as long as he works hard he should iron these issues out and truly blossom over the next couple of years. Being the senior England national team CB can only help.
Laporte is a mix of all the others. He can play the aggressive game like Otamendi, in that he can get high up the pitch and win all manners of tackles, headers and interceptions. He's also got his confidence of bringing the ball forwards. He can defend deep like Kompany, in that again he can win key headers in defense and attack, make super important blocks and clearances as well as the odd last ditch tackle too, on top of matching his technical ability going forwards. Not to mention he's got Kompany's desire and leadership traits. And like Stones, he plays with a certain assuredness and composure defensively that makes him sound, as well as being great at finding those passes that split the lines. I wouldn't say he's as good as any of those three in those regards, but he runs them close in all senses and that's amazing. The only downside is he also is a mix of all their weaknesses. He gets overly excited like Otamendi and makes over-zealous plays in attack and defence. He gets clumsy like Kompany and makes dangerous mistakes and shows the same kind of youthful errors of judgement that Stones does. Such an incredibly all-rounded defender though.
The fact we have four CBs who would each not look out of place at any club in the world is a remarkable achievement by all involved.
