@Kaarme Having been on the same side of this issue as PLG, I can only add one thing.
Kouka, Xing, Sei and Kai are a cultural continuum. Same language and similar customs.
Suppose Kouka got invaded or peacefully annexed by Kai due to King Il's inaction. If it were for the sake of peace, so what? You talk of poor foreign policy on Il's part, but poor for whom? The people in the former province of Kouka that Soo-won retook in chapters 95-100 didn't give a damn to who ruled over their lands, so long as there was no war. Ditto for the villages in Sen Province where Yona and co. found the Iza seeds. They had belonged to the Fire Tribe and yet their festival was meant to appease the ire of the Fire Tribe. And they got the Iza seeds from Kai. So they were better off under Kai than under Kouka.
See what I mean? The worst peace is better than the best war. Soo-won's warmongering only serves his own mental construct of Kouka as an indivisible unity. But even the dissolution of a country, or its annexation, if by peaceful means, are better than wars to maintain national unity. The examples in the story show that the people abhor war more than anything else, and that a change in overlords doesn't necessarily change the commoner's lives for the worse. So yeah, Il's meek peace ideal probably cost fewer lives in his reign of about ten years than Soo-won's ten months or so of war and strife, especially if we include soldiers, who also happen to be humans.
In fact, the scorched earth wars we're used to are relatively recent. There have always been exceptions, like the Mongol invasion of Persia, but before standing national armies appeared, war was a business of greedy nobles and the people just wanted it to be over. Total war is an invention of crazy European elites.
I'd also add that Geun-tae, Joon-gi and Soo-jin held as much responsibility by the decadence of their tribes during Il's reign as the king himself. Kouka is described as a federation. Soo-won having to tell Geun-tae about the commercial potential of
his own wife's tea (!!) tells us more about Geun-tae's incompetence than about Il's, or Soo-won's competence.
So yeah, I see no evidence that Soo-won would have led Kouka down a better path had it not been for his failure to kill Yona. He was extraordinarily lucky in her survival. But of course, neither you nor I can be sure of that, because it's a counterfactual. I'm just pointing out that just as you can choose to believe he'd be able to sort all these problems out even if Yona had died, I choose to believe Kouka would have become a meal for the dogs of war had she not been there to steer the country towards peace. What we have that is not counterfactual are the facts of the story so far, which show that she's been the only force for peace in this country after Soo-won usurped the throne. And that trumps every single domestic policy point he has score, in my opinion.
Last but not least, as I always suspected he would, he's now playing to attack Kai for no reason. That's one brutal and unnecessary war, much like the one he waged first. I really hope he kicks the bucket before that happens. That illness is more than welcome, though I'd prefer Hak to split him in two.
