Manchester City had a rocky start with Pellegrini at the helm, but I am positive they will be much, much better footballing side than what they were under Mancini.
However, if I have to criticize one thing about their transfers during this summer is the fact that their reinforcement in midfield weren't enough. Fernandinho is a step in the right direction, and I think he will come good, although he is struggling with his adjustment right now. But they need another 1-2 top class midfielders. Javi Garcia isn't that, and now, I think he is considered a defender (a bad one). Barry isn't top class, neither is Rodwell. Milner can do a decent job, but again, not top class. Yaya Toure has only a title that says he is a midfield, he became a very undependable one.
So instead of buying Navas, Negredo and Jovetic, they could have, and indeed should have, bought a top midfielder. Knowing Pellegrini's teams, I am surprised he didn't buy a ball playing possession style midfielder-playmaker. I know, he didn't have one in Malaga, but that's because he didn't have money. Watching a porous midfield get dominated by the likes of Hull... this is not what I expect from a Pellegrini team. Fernandinho, even if he comes good, won't do this alone, and Toure is no help.