I think the big teams prioritise the PL & the CL, it’s difficult to compete & try to win the domestic cups too. Only really Man City have a big enough squad to go for everything.
Manchester City does have a complete army. I believe that Man City in the domestic league is very impressive, but in the Champions League they don't have the mental strength to do it. It has been proven, they are not able to compete in the champions league.
Their team is absolutely complete in all positions.
In my opinion Manchester City lacks of European football culture. If they add this variable to their play style then they are be a challenger for the CL title.