His diagonal balls are spot on.
I am at the point where I would be more than okay with us going into next season with Pique, Lenglet, Araujo and him. Defense quickly went from being our 2nd biggest problem to being quite okay - at least personal wise thanks to Mingueza.
I think he has been much better at CB than RB so far. He had one terrible game as RB where he looked slower than Busquets, and he is showing time and again that he isn't great 1v1 anyway. Offensively he is a bit rough, but can do it decently, not very far from Oleguer, or maybe somewhere in between Oleguer and Puyol when he gets forward on the flank.
As a CB he has more passing lanes open and have shown a great calmness and ability to pick the right option from there. He is also good at picking the time to press or intercept from an attacker with his back towards the goal. I think the back 3 suits him very well, but he had great games as a CB in a back four as well.
I don't know that his potential is huge, but he can play. Bartra could play as well.
In a 4-3-3, where would you play him? At the moment I think he'd be better as a RB than a CB. Surprisingly very good on the ball under pressure.
But his potential at CB is huge, although very hard to reach with his current flaws.
He's like David Luiz, who was once PL's best CB, but most of his career he's looked like a clown. That's what you get from that type of player. Reminds me of a young Ramos as well.
Sooner or later he won't be able to rely on the 'safety' of playing in a back 3. That's his last step in development.