The Ending: Simon gets away scot-free but a bitter John McClane - now forced out of the NYPD following the events in the film - tracks him down some time later and forces him to play Russian Roulette with a rocket launcher. Simon loses and shoots himself in the chest only for McClane to reveal that he was wearing a flak jacket all along (which could presumably withstand a rocket launcher?)

If They Had Left It In: The over-the-top Russian Roulette seems a bit silly but McClane as an angry, fired cop? That could give him a certain edge that he's been missing in the more recent films.