There are only a couple of scenarios where I'd use VAR and they all involve ejection-worth offenses. Apparently Zidane wouldn't have been ejected in the WC final vs Italy if the refs hadn't seen his head-butt on the big screen??
I don't like it for Offside and I HATE it for reviewing penalties. Awarding a penalty kick changes the game so much, it's often so subjective, using replay gets to be a disaster. It's always going to be a controversial decision, introducing replay into it makes it 10x worse imo.