I think when you look at the players they signed though they'll know their roles. Taking Fernandinho, I'd say he's better than Garcia, Barry and Rodwell in that position. Added to the fact Toure tends to get exhausted every season once they lose him, or his presence, they seem to struggle a lot so you'd imagine that allows them potential to rest him and not lose as much quality as they did. Navas I'd again argue is now their best, or at least most productive, winger. The other players who can play there, Sinclair, Milner, Nasri and Jovetic aren't as good as him for me. Sinclair never gets a look in, Milner is just a "steady" option and Nasri isn't really at his best on the wings. Navas will give them the pace to get up and down which they lacked at times. The other 2 I'd agree are squad players but Negredo will get goals I'd imagine and Jovetic is a young player so there's potential there.
I think the problem with the spine of their team you've got there is only 1 of them performed consistently all season and that was Kompany. Hart made about 5 or 6 big errors, Toure and Silva looked fecked by the new year and Aguero never recovered from his injury in September really. It seems like they're making assurances that they've got quality in the positions so them players won't go a miss. We're fortunate Carrick and RVP stayed fit all season for example as without them (especially carrick) we'd of struggled big time.
I think you sum up part of the problem with the 110% for the shirt point. City know that most of their players aren't arsed about the club, but that's the same for most football players I'd imagine, they will be in it for money really. But in order to get the big money they've got to perform. City identified that most their team, and their spine, didn't perform so had to sign players really.
I agree to an extent with your last point but that should be what footballers are like. You should care you've been left out as you then strive to improve. If a player was happy to sit on the bench for 38 games a season then they shouldn't be in the squad anyway, these players should give them the motivation to up their game. City for me last season were very very average, sure the players like Silva and toure have the ability to get back to their best but when there's no direct competition whats your incentive to do that? You know you'll definitely play, at least now if Toure plays poorly he knows that Fernandinho may take his place and slot in alongside a Barry or Rodwell. If Silva plays poorly there's potential now to use Jovetic there, same with Aguero and Negredo.