Yes all your ponits definetley make sense but sometimes people's past shape their future. He was tricked by the Heavenly Empress and he was always blamed for the things he didn;t so. Xu feng was spoilt and treated nicely while Run yu was just a bastard. Just because he tricked her doesn't mean that his feelings for her were not genuine. He saved her countless times, and gave her mercy when she tried to save Xu Feng. He did many bad things though and his past can't justify all the things he did. If you think about it carfully though he was getting revenge and wouldn't you be doing the same thing if all the same things were happening to you, again doesn't justify his actions though. You can't really hate him though cause he has a good reason for this but the emperor, empress and other girl who likes Xu feng had no way to justify their actions.
Please rest in peace and I hope you are happy wherever you are
Anyone know where i can find it been waiting years