There is a number of very good editors about for the PC and 360 for editing teams, players and stats.
These make editing the game a lot faster as they allow things like universal stat editing, ie - you can edit all players stats at the same time.
This makes changing the gameplay much easier, for example if you add 10 to the aggression and teamwork stats of all players the game will be a lot more difficult as you will get less time on the ball and the other team will be more intelligent.
There is no editors such as these out for the PS3 version of the game as the saved game files cannot be read
These make editing the game a lot faster as they allow things like universal stat editing, ie - you can edit all players stats at the same time.
This makes changing the gameplay much easier, for example if you add 10 to the aggression and teamwork stats of all players the game will be a lot more difficult as you will get less time on the ball and the other team will be more intelligent.
There is no editors such as these out for the PS3 version of the game as the saved game files cannot be read