Personally, before I make any final decisions, what I really want to know is what the REAL intentions of the priests are. Not the surface ones, but the ones hidden behind the smile. It's already been stated that both the royalty and common people didn't approve of the priests interfering with the government politics as much as they had, and the last chapter clearly showed a small piece of their religious control on the king's family with Il. Not to mention, has anyone else even considered why exactly Yon-hi's people were living in hiding as they were? I mean, they are King Hiryuu's blood descendants which for all intents and purposes makes them the true royalty of Kouka, so what was the reason they ended up in that situation? Regardless of them having short lives, something rather drastic must have happened in the past for Il and Yu-hon to end up as Kouka's current royalty. This is a really big missing piece of the puzzle that I'm afraid we're not going to learn about but would certainly explain the priest's border-line creepy interest in King Hiryuu's descendants. Most of our history shows us that religious leaders will usually make use of things related to their own gods to further their agendas, so what did that priest really plan to do with Yon-hi's family? Depending on that answer, Yu-hon's actions might actually be justified.
Not to mention guys, I hate to say this and I certainly by-no-means do not approve of his actions, but if Yu-hon hadn't actually played the role of a violence loving villain than Kouka wouldn't be enjoying the peace it has right now instead of ongoing wars from the other neighboring countries. Remember how it's been mentioned that the other countries like Kai, Sei, and Xing were all extremely terrified to start anything with Kouka because Yu-hon was there and they had previous experiences on the carnage he could cause? While I certainly feel bad for people like Princess Kouren who suffered greatly because of him, I kind of pity Yu-hon in all honesty. Kouka is completely surrounded by those three powerful nations who would all equally love to conquer Kouka but in order to keep them at bay, someone like Yu-hon was needed to make sure they feared what would happen if they tried. The poor man probably has severe PTSD from everything he's had to do in order to ensure that his country wasn't ravaged by war. This just my own personal opinion.