Not sure about the sin bin thing before I hear more but one thing I think Football has needed for a long long time is allowing only the captain to approach the referee.
It's frustrating to watch when a foul or something happens and then you get half the pitch sprint over to the ref to try and influence him into making some kind of decision.
Having the ref's micced up so you can hear a conversation between them and the captain would make for good viewing whilst also improving the overall game I think.