Just my opinion but i do think we need another centre half (but i would rather it not be Maguire)
Ottomendi is mistake ridden - he had a late bloom in the season before last but before that he was prone to regular mistakes and isnt good enough with the ball. He makes very rash challenges all over the park and is very slow. He is a fantastic competitor but just isnt good enough.
Laporte has been outstanding so no issue there
John Stones - has mostly done well - but is he a leader -- he just doesnt appear to be but he could grow into that...His physical side of the game needs to be worked at as he is vulnerable and can get dominated..With the ball he is mostly excellent.
Therefore for me we have two first choice centre halves and a back up who just aint good enough.
We then get to players playing out of position (nothing wrong with that as Zinchenko has proved).
Ferna - fantastic player, good with the ball, reads the game well, good in the tackle and for a small guy is good in the air but he is coming to an end and Im just not sure about him playing there (epsecially if it was regularly due to a long term injury)
Walker/Danillo - just no - they will put 100% in and their pace (esp walker) is useful but they are far better fullbacks than centre half
Taylor HB - This kid looks the real deal but he is 17 (i think). I havent wathed the EDS but his pre season has been impressive...if he was a fullback you could maybe get away with playing him in some games but could we get away with playing someone so young in such a key position.
Its not just Kompany's ability on the pitch that we will miss but his leadership - i dont see another charachter int he squad that can replace that at present (maybe Ferna or KDB)
Overall i think going into the season with those options at centre half is a huge risk...one long term injury and it really is square pegs in round holes.....though again Pep (and zinchenko have proved that this can work to great affect....
Maybe a switch to 3 at the back regularly?