It has often been said that the best leaders one can have is a omnipotent benign autocratic monarch, or popularly known as "the good tsar". But the flip side is that the very worst human leaders is "the bad tsar".
Mathematically you are bound to run into a bad tsar much more frequently in a hereditary succession of political leaders, and besides, n-th generation descendent of great leaders are far more likely spoiled brats, black sheeps, or worst, lunatic ideological socialists. (It has been repeatedly shown that sons and daughters of mega-riches with political interests tend to be the most leftist politicians you will ever see)
It is just not worthwhile to have such a system where people are put to ransom UNLESS as you say we have a perfect, merciful, and just King of kings, Jesus, ruling over the entire world. The Bible says such a Kingdom on earth will come in the future. I will gladly accept such a Kingdom because we will then have a perfect system of government.
Christ's Kingdom will be filled only with people who WANT to obey.