oozihobo, that is a great example of how a single major pro can outweigh a multitude of minor cons.
edit: also, i don't believe that self-policing or even leading by demonstration works in the real world, because they are so idealistic. not idealistic in the sense that there are ideals that we should strive for, but idealistic in the sense that your solution y is conditional on you first positing "in a perfect world, where x is the case, y follows." x being human nature not entailing the primacy of stubbornness/self-interest, and y being a system of government that does absolutely nothing to infringe on its citizens' freedom to act in any way they wish as the best form of government. of course if it were somehow guaranteed that if all people were perfectly good and rational, and would always be, then government to any degree would be undermined and superfluous. but precisely because x is not the case, anarchy doesn't constitute a foundation for a happy society. for society to be sustained, its people must at a minimum surrender a portion of their autonomy, like their otherwise unmitigated freedom to go steal and kill.
i also understand that you propose these as ways to improve the status quo and not as solutions in themselves, but if we are honest about the existence of certain problems and willing to face them, then we really should be looking at their underlying causes and their respective solutions, not ways to make an unappealing system less unappealing.