I think it definitely needs to come in. In this day and age it's fecking needed. The game is just so so fast now.
There should be an appeal system. Say each manager has one or two or three moments in every game when they can review an incident.
The only problem with that system is that, if your team is about to be hit on the counter attack, what would stop you calling to review an incident?
I'm not sure how it should actually work, but something needs to be done, even if it's just a chip in the ball to determine when the ball goes over the line, it's a good start and wouldn't interfere with play.
Ball goes over the line, the chip in the ball triggers a sensor, fireworks go off behind the goal, everyone know's a goal has been scored.