i would introduce var and use the tennis system where each team can only use it a set amount of times during the game and if their VAR review is rejected then they lose the chance to use VAR again
I would also introduce a blanket rule on penalties - once a penalty is saved or if it hits the woodwork then the ball is automatically declared dead and anything that happens afterwards does not count, the game will just resume with a goal kick. That means that there will be no second advantage of a rebound, 2nd corner or a fortunate mishap if the ball hits the bar then the keeper and goes in.
in a penalty shootout you don't get a second bite at the cherry do ya, so why should you during the match?