Concept is awsome but needs some work.
Well I found the game fun but aggrivating because the controls could use some work. when you try to over simplify the controls like you have you run into the problem of having to many opptions on a to small amount of keys. I would suggest seperating tackle, throw, pass, and change player to seperat keys so that when a person takles an opponate they dont also send the ball flying because they throw it right when they get it.
Also the passing system needs alot of work. Its fine if your passing to a person that is directly infront of you however if they are farther away or at an angle they usualy run right past the ball and you cant stop them because the switch player doesnt allow you to switch to the person getting the ball till its going right by him which usualy results in a mad dash to get to the ball before it rebounds of the wall into an opponates hands.
Another flaw is that when trying to pass the ball at an angle into the goal it seems the ball bounces off of a corner thats not even there. If your going to make the corners rounded make sure that the game knows they are rounded.
besides those things the costomization options are awsome, the "plays" are great, and it is rather fun. A feature that you might want to add could be powerus (i.e. spped, super tackle, etc...)
~The Cake has spoken