In the current squad-
Bravo (I think he's underrated just because his name's not Joe Hart)
Caballero (I think he's a legend who should stay here until he retires and actually a far better goalkeeper than most PL #1's)
Otamendi (Love him even if he is hugely flawed)
Kolarov (Think he's got a great personality and presence but too inconsistent on the pitch)
Mangala (Would've liked to see him get a chance)
Delph (Decent player who's too injury-prone to make much impact)
Fernando (Could write a book about this- one of my favourite City players and someone we need if we want to win the league this season. Hugely underrated IMO)
Nasri (In terms of raw talent, one of the best in the world. In terms of attitude and workrate, not good enough)
Bony (Clearly a good player who needs to be in a system that values him. City's directors of football made a terrible mistake signing him)
And weirdly, the player who perhaps is most controversial amongst City fans is also one of the nicest, quietest and most polite footballers out there by all accounts: Jesus Navas.
In my opinion, Navas is a crucial player. He is unrivalled in three crucial assets: Workrate, passion and speed. He's technically very good and does put in some great crosses, and he creates goals.
On the other hand, his final ball isn't great, his confidence is very low and he's not the tallest nor the strongest. But the personal issues he overcame to come to City, plus the fact that he will always do his best for the team, means he's a player I will sorely miss when he is no longer at City.