After playing countless City saves, here are my thoughts on the squad and my general first window signings. (I play a 4-1-3-2, no wingers btw)
Strikers
City are stacked to begin with. Dzeko, Tevez and Balotelli are first class. Adebayor, Santa Cruz and Bellamy need to be sold ASAP, but generally I can only get rid of Adebayor and sometimes one of the other two. I generally sign Cavani in the first window since he is the best young forward in the game in terms of all around skill. My "A" starting strikers are Cavani and Dzeko, and my "B" strikers are Tevez and Balotelli, with RSC or Bellamy as the 5th striker in the event of injuries. Longterm I always sell Balotelli because he is just a constant pain in the ****, but I never sell him the first season. You can drive his value up by keeping him and letting him score plenty of goals against lesser teams in the cup competitions.
Midfield
I sell SWP and Adam Johnson in the first window. I play no wingers, plus neither are really elite anyway. I always buy Sissoko and Pastore in the first window. Pastore is one of the best young attacking mids, and serves as Silva's backup. Sissoko is arguably the best young DM in the game, and I develop him behind De Jong for a couple years. Otherwise, Citys existing mids are more than good enough to win trophies year one.
Defense
Here is where I make the most changes. I always sell Toure and Onuoa, and depending on Boyatas initial stats, I consider selling him as well. I buy Chilleni, Kjaer and Phil Jones to immediately lock down the center of defense. Chiellini and Kjaer are my first team starts with Jones and Kompany as my second pairing. Richards/Zableta on the right and Kolorav/Lescott on the left are good enough to win trophies from the start so I generally leave them be and invest elsewhere. During the second window I sell Lescott and Zableta, and upgrade at LB to Bale and either get Rafhina or Rafael, depending on their stats for that given save. Richards can be a longterm starter, so I generally prefer to sign a young RB in the second window to back him up, but sometimes Rafhinas stats are so undeniable that I sign him and let Richards back him up for another 2-3 years.
Keepers
Hart is a solid keeper and Ive had plenty of saves where I just use him for the entire save, but I generally sign De Gea first window to get him in intense training. De Gea is a monster in the game, so I generally like to have him from the start and have him backup Hart season 1, and then move him to start in the second or third season. between Hart/De Gea you dont have to worry about keeper again for the entire game.
After first window...
1st Team
-------------Dzeko --- Cavani -------------
----------Milner --- Silva --- Yaya ---------
----------------- De Jong -----------------
Kolorav --- Chiellini --- Kjaer --- Richards
------------------ Hart --------------------
2nd Team
------------- Tevez --- Balotelli ------
---------Barry --- Pastore --- Denilson*----
-----------------Sissoko -----------------
Lescott --- Jones --- Kompany --- Zableta----
--------------- De Gea ----------------------
*** I list Denilson here only because he is in my current first season save. I generally get another mid after the primary signings, but that can change depending on stats for that given save, plus available cash. Ill generally watch Denilson, Rodwell, Ramsey, Wilshere etc and go with whoever can be had.
First window buys:
Cavani
Pastore
Sissoko
Chiellini
Kjaer
Jones
De Gea
***Misc mid
First window sales:
Adebayor
Santa Cruz
Bellamy
Viera
K Toure
SWP
A Johnson
Onouh
Boyata (Depending on initial stats)
M Johnson (Depending on overall mid depth)
Given
Second window I generally sell Balotelli, Lescott, Zableta, whichever striker I couldnt in the first window (Bellamy or Santa Cruz), M Johnson and possibly Barry depending on mid depth. Ill generally buy Bale, Rafael or Rafhina, Lukaku, Hlousek, and some combination of Rodwell, Ramsey and Wilshere. By the end of the second window, your team should be unstoppable and you should have enough young talent to dominate for 10 years with that primary team.