It will be nice to see again the player attribute “aggressive”. When a player very aggressive make a cross, you have a very high chance to make injuries, get a card or make another opponent agreessive player to confront him and, if the referee is very strict, may be both get a yellow or a red.

It also will be nice a cheating button:
that allow a player with possession of the ball to simulate a foul.
Or if its not a good header and is surrounded by good headers, to use a hand (like Maradona). Sometimes he will get the goal (depending on the position of the referee), the rest of the times he gets a card.
It will also allow a defender to destroy a 1-2 pass by hitting the receiver. Again, sometimes nothing happens, sometimes he gets a foul with card or not depending of the position in the field
It will allow to stop a lobber using the hand, very useful to defend some dangerous and deep pass.
Running from behind it allow to grab the opponent from the t-shirt.

Sometimes when two players collide trying to head the ball, some of them will remain in the field knock down until the ball goes out or the referee stops the game.

I’ll like to see goalkeepers getting out of the area to stop an attack and use the cheat button to stop the ball with the hand outside of the area.

I like FAIR PLAY, but is not real and I want a realistic game.

A definite yes, all that would be awesome. i think EA wouldn't be able to pull it off. They have enough problems as it is with realism in the basic game. Until they fix that, then i hope they can step it up with your ideas!

Live Long and Prosper

How about keepers who actually get fouls against them... and sent off for being the last man!

That could make for an interesting penalty kick!

that allow a player with possession of the ball to simulate a foul.

You can do that on Fifa 99, the greatest of the EA editions