These kind of series are exactly why the monarch filled Europe had strict succession laws and no polygamies, no harems and whatnots. Any succession crisis always lead to a huge mess that sometimes spanned the whole bloody continent.
Can't even say that the harem method of "survival of the fittest" was effective, when you look at the Ottoman empire. They got a few shining jewels out of it, but on the average it just resulted in fierce in-fighting and bloody slaughter to take care of any rivals of the padishah.