This is my first post. I normally just read other comments. You definitely have to keep him. It's a good thing fans don't run the club. Big clubs don't sell their best players. He and his agent are clumsily trying to get a wage increase. City is in a position of strength because he has 3 years left on his contract and he is 31. C. Ronaldo did the same thing last year when R.Madrid would not make him the highest paid player in the world. He told the press that he was sad. The club eventually obliged. Messi also had complaints abut eventually signed his contract extension last week making him the highest paid player in the world.
When Rooney did the same thing , many United fans wanted him sold because he "disrespected" the club. The same fans are cheering for him now. It seems like the best players world sign a contract extension every year. Especially after having a great season. Central midfielders who score 20 plus goals in one season don't grow on trees. Yaya is the only midfielder who did it this year. No other midfielder in Europe even came close. The club is very capable of dealing with him.
Finally, we can't compare ourselves as fans to one of the top ten players in the world. These are uniquely talented footballers who are wired differently from the fans. They can be petulant (Rooney, Yaya, Ronaldo etc). However, if City fielded 11 James Milners or 11 Pablo Zabaletas, the club would have a hard time finishing in the top 10 in the premier league. As petulant and egocentric as Ronaldo is, does anyone think that R. Madrid would remotely consider selling him even for 200 million pounds. City's owners, management team and if need be Pellegrini will deal with Yaya. No way they are selling him. Tevez and Balotelli were different. They didn't get along with the coach, didn't want to stay in Manchester. Yaya is just looking to be shown some love because of the spectacular season he just had. The higher-ups at the club should be able to deal with him and his agent and they will.