It’s worst when a player is deemed (or not) to have impeded the GK in an offside position. Hugely subjective.
Give VAR 10 seconds to challenge the on field decision. If that’s not enough time then it isn’t an obvious mistake so let the game continue. There would be some ‘tight’ errors made (as there were before VAR) but the games would flow and the obvious errors removed. I’d be happy with that.