I know how you feel. I usually play characters into being polite and tolerant to certain extents. But when I got to the part where the King, a man who refused to be part of Leto's life, pretty much badmouth the other side of Leto's family and look down on him like he was a thing rather than a person, I immediately went "Oh heck no" and had Leto be defiant toward him. No amount of patience, kindness, or blood relation would let me tolerate that clear disrespect and hatred from that King. If that's how the interactions with the King begin though, I have to admit, I'm very curious to see how the Seventh Heir's half-siblings will interact with them as they get older.
That said, I'm going to enjoy making Leto an intelligent strong heir who is polite and kind to others, but defiant and aloof toward the King and those who he feels deserves it.
Strangely, this song ended up as I played the story and thought about Leto's eventual involvement to the more political ruthless side of his noble life: