I disagree that all problems persist. Some, like you mention cronyism, indeed tend to persist. But the predatory attitude that a politician has toward his own country will go away. What king will put his country in hock as deep as our presidents do, in times of no military threat of invasion. Who would let people without any cultural attachment to the blood and soul of the country come in to support the national pension plan? Who would let the domestic industry be shipped off to China? The sheer idiocy of the political decisions, precisely in industrial democracies, are without precedent. That is a direct consequence of the fact that the mental horizon of a politician is about 4 years, and a monarch works for his great grandchildren.
I agree that the spirit of the day is not good. It is a theoretical conversation. My hope is to get people thinking that maybe not all the propaganda their country stamps into their head is for their good; maybe this visceral hatred of monarchy is the left wing, who dominate the education, busy smearing their biggest enemy: the nationalists, the religious, the monarchists.
So it was with democracy or republicanism. And now it's the supporters of monarchy's turn to paint it in idealistic colors and argue that it's free of the usual corruptions of politics.
Monarchy now is a little like the direct election of senators. People promote it as a cure for what ails us. But society and people's thinking is already highly democratic.
A monarchy couldn't be put into place if it weren't, like Britain or Spain or the Scandinavian countries, essentially window dressing for a democratic or republican government. A king wouldn't last unless there was a representative government in place and in power beneath him, just as senators wouldn't have much real power if they weren't popularly elected. If a monarch really tried to act like the monarchs of pre-democratic eras he or she wouldn't last long.
Do kings and queens have a wider mental horizon? Sometimes. Some do think in terms of centuries, rather than 4 year election cycles. But in a hereditary system there are bound to be lemons. Sooner or later a Marcus Aurelius is succeeded by a Commodus. And there would be more lemons if monarchy were truly established: kings are so well behaved now because they realize how fragile their rule really is.
Are kings more attached to national values? Once upon a time, everybody was. Once upon a time you wouldn't have had rulers thinking that development in India or China could offset decline at home. But now you have people thinking that, and why would a king think any differently, especially when you consider that in their heyday kings and queens were accused of thinking more dynastically than nationally?