And in exchange for this "safety valve" you get the potential for absolute and unreviewable corruption by giving one person the authority to arbitrarily override the judicial branch at will. And to do the same with the legislative branch through executive order.

If America mistrusts government so much that it wants the President to be a de facto monarch, it should just drop the pretense at being a republic and have a monarchy already. Or make the oligarchy official and elect a CEO in chief. At least then there's only one head for the CIA to put a bullet into.