So your best argument against the Brittish monarchy is that Harry dressed up in a Nazi uniform as a parody when he was a daft student and you think you believe in a crazy conspiracy theory about Diana being murdered by somebody but you don't know who or why.
You are still ignoring my post so I will paste it for you below the line. You could use it to have a mature discussion or you could continue with ad hominem comments and lol's.
There is one main reason why I think there is an advantage in our current system. I can rage against the decisons of my elected government but still feel patriotic and find common ground with others who hold opposite views. During the Iraq war Americans who pointed out that it was an illegal war were made to feel unAmerican. In the UK we had no such problem. Our troops can bitch about being sent to fight in an unwinnable war in Afghan and dragged in to do security duty at the olympics because the government failed to supervise the G4S contract but they still serve the Queen who remains aloof of the politics. Having a non-political commander in chief is very significant to the armed forces. Its symbolic, its a bit tenuous but I think its valuable.