max, I think what you're getting at is that people need firm leadership. It's comforting to know who's in charge, and having someone to defer to makes life easier in a lot of ways, and lightens the burden of individual responsibility. Individual responsibility is one of the greatest gifts the Enlightenment gave us, but come on, let's be realistic -- no individual can take full responsibility for everything he's involved in, because his knowledge base doesn't extend that far. So the role for leadership and chains of command is not entirely obsolete at all, just diminished.
To me, "king" implies a large amount of power concentrated in the hands of one individual, to the detriment of his subjects' ability to exert much influence at all upon their own lives. That is definitely a step backwards, and ethically highly questionable in this day and age. That said, look at ideological cults of all sort -- if people in this day and age are given the free choice to be free or be subjects, and they freely choose to supplicate entirely before a king of their choosing, then it's hard to feel bad for them. Being born into a system where your entire destiny is in another person's hands, in a world where there are other options available, now that's a stickier issue.
I have no issue in principle with figurehead kings / emperors / arch clerics like the pope, so long as their actual powers are quite curtailed, and citizens have the right to openly disagree with what they say.