I agree with most on here that Aguero is twice the player Jesus is right now. At this point, he is still our most reliable goalscorer and a player I believe would be extremely hard to replace.
I would question how reliable a goalscorer he is these days. This is probably the heart of the problem Guardiola faces too.
2 goals in open play since September.
Last season he only scored 6 goals in nearly 6 months between September and March.
When he's on it, he's the best striker around, but you can't go months without scoring and be a reliable source of goals, and these days I'm not sure how often he's really on it.
Mind, none of them are sharing minutes with other players.
Bit of a chicken & egg situation that - if Aguero was putting up their numbers he wouldn't be sharing minutes.