Here is my guess and analysis.
IMO Mancini will most likely get fired, what happens after that is for me pretty obvious regardles of who replaces the italian. But first, a short analysis of the season.
City started of fantastic, absolutely fantastic. Scoring goals, creating chances; nobody could stop the blues. Comparitions to Barcelona were made, and with good reason. The style of play was somewhat similar. However, this came to a sudden stop slightly before/after the winterbreak. If you look at Citys last 10 games, the lack of chances created are shocking.
What happened? Like Barcelona, City wanted to attack through the middle. The man in charge of the last pass; David Silva. David Silva was brilliant before the winter break, possibly the best player in the league. But after the winterbreak he went from brilliant to mediocre, while City continued the same style of play; through the middle. IMO this is when Mancini should have implemented a wide alternative(more play on the wings). I also think more focus on wing play will be in the book of whoever replaces Mancini(if that happens)
How will City look like next season? Balotelli will be out of the big picture, either sold, or replace Dzeko on the bench. I don't think Tevez will leave, unless he shows willingnes to do so. Adam Johnson(if he stays and he should) is going to play a decisive role, he will become a starter, playing on the right wing. On the left wing I think a new manager would play Kolarov, or possibly buy a left winger. Why so much focus on the wings? City need an alternative to the constant play trough the middle. Also, Edin Dzeko will be used entirely different than up until now, being a striker up front, getting fed from the wings.
This is what I think the attacking line up will look like:(from the left)
LMF Kolarov/new player
DMF Barry
CMF Yaya Toure
CMF Silva/Nasri
RMF Adam Johnson
SS Aguero
CF Dzeko
To clear things up. I am not saying that City should stop playng possesion football and attack through the middle. However, some games have been down right pathetic to watch where City constantly try to get through the middle without any plan what so ever. Also, with a player like Dzeko, playing with wings is a must. Feed him, and he will score.