To be honest, I would not want video evidence to be brought into football at all, football is a different game to rugby and say cricket, where there are many stoppages in between the game for the video ref / umpire to review the incidents. Football is a non stop free flowing game (supposedly) unlike the likes of Rugby where there are minor stopages here and there. By having a video ref, it will definitely disrupt the flow of the game, at the same time leaving fans in the stadium or watching around the world impatient while waiting for the decision.

I am all for goal line technology as it could be a simple ship and sensor that beeps into the ref's head piece or an indicator behind the goal that indicates whether it's a goal or not.

I am actually very interested to see FIFA revive the plan to have 2 referees, one in each half like hockey. Most errors in desicions are a result of poor positioning (Rob Styles' "penalty" against Liverpool), tiredness and not able to keep up with play. With player running faster and stronger these days, it is not unusual for the ball to be at one end of the file and then the other end in less than 10 seconds. To be able to keep up with the play, unless the refs are all olympic sprinter with an eye like an eagle, there's no way they could keep up with the play all game long. Not to mention is the team employs long ball tactics which will see the team pinging long balls again and again to launch an attack.
With a referee in each half, it is easy for both to keep up with the play as they would only worry about the play in their half, thus minimise the error through poor positioning and tiredness. This could even be expanded to have 4 assistant referees with two on each half of the pitch, right and left flank, that way, it will also help to eliminate incorrect offside calls.

Many a times we see incorrect offside calls are made on the play happening on the opposite flanks rather than the near flank, or plays starting from opposite flank to the near flank, by having two assistant referees, it will help the decision making process and help the referees in making a less erroneous decision.

Granted, many would argue that it is still human and error will be inevitable, there will be a big revamp of the organisation and referee set up to make this work, in deciding who takes care of which side of the pitch etc etc. However, it is always the human element of football that we enjoy the most, giving us plenty of talking points to debate and discuss about during the week. Imagine a place like LYn if everything is computerise and every decision made by the referee is spot on, we wouldn't have a lot of banters and debate in the forum, how boring.

You left out the customary "Howwwzzzzzaaaaaaaattttttttt!"