I think Sedin is still a pretty flat character and his initial interest was out of hunger for power (pretty hilarious to me but it's never taken in a comedic way here), which can be dangerous, but god knows how he feels now. At least he's still better than the prince.
Speaking of the prince...I feel bad for him to have that kind of parents and pressure, but it isn't right to treat Renee that way just because he saw himself in her. Perhaps he's acting kind now partly to make up for all the time he treated her poorly, but I kinda doubt it. Also, Lian is still quite similar to him, I think, in which the two actually don't hold any power on their own. They're just puppets of the church and emperor respectively and that's sad.