The way it is currently used there is no point.
1. Keep goal line technology but double check some fucker has actually turned it on and it's working.
2. Sack off the offside decision. Leave it to the lino, you'll win some you'll lose some.
3. Immediately get rid of the rule about not flagging, when it is blatantly offside, until that phase of play is over. It wont be long before an injury occurs as everyone is going full tilt for no reason.
4. Check foul play if it looks like a serious injury has been caused but the ref can only look at the monitor for 45 secs max and it has to be at full speed, none of this slowing it down from every angle and zooming in. If he cant decide in that time go with his original decision.
5. Explain what the fuck the green zone is. Was he actually watching the game or accidentally had his mic turned on while watching a film on the Iraq war.
6. Checking goals should be a 20 second look. If nothing is glaringly obvious you go with on field decision.
Finally, with VAR, what is the point of the linesman? The don't flag for offside until the play is over. If one team scores it gets checked, if they don't who cares play on - so no point in them.
They never seem to flag for fouls. If there is one the ref gives it or if anything significant happens after VAR checks it - so no point.
And I'm sure deciding throw ins can be done without their input 95% of the time.