How would we choose a king/queen? By vote, divine right, trial by combat? What would determine who would succeed them if they're deposed?
Why? Britain's king/queen is largely a national joke. They have no real authority; just a pampered lifestyle. Britain's power is vested in its lawmakers and courts. Their problems emanate from those.
What we need is an emperor. He will be chosen from the following criteria: 6'6" tall; green eyes; he will neither drink nor smoke; he was born in Louisville, KY; he has multiple college degrees; he has a motorcycle sitting in his garage that he hasn't ridden because he has neither current tags nor title; he loves guns; and he has back problems.
The above criteria sounds good to me. We give him absolute power. Problem solved.