Chignon wrote...
john-in-france wrote...
/snipped for length
It is just an opinion...not game canon, codex or wiki, just a writer thinking aloud.
On that I agree, but I'm not as much disagreeing with your opinion as I didn't understand the connection you've seemed to imply between a rivaled Sebastian and him "going crazy".
Not so much crazy, but rivalled Sebastian and a live Anders at the end. I think it could shatter something...namely the veneer stopping the old Sebastian from surfacing.
Do you have the writers psychology/mythic models book: 45 Master Characters?
It took me 2 hrs to realise that these archetypes were alive and well, and our companions in Kirkwall. It even has a section on friendship and rivalry.

Now Sebastian is a main type combo Messiah/King. These are direct quotes...In your head swop Divine for Maker.
Messiah type:
Because of birth he doesn't have first hand knowledge about the inequalities in the world and needs to be educated in them (aside: take Sebastian everywhere).
Every living thing is a manifestation of the Divine to him.
He cares about others recognising their own divine nature.
He reveres healing the soul above the body.
He fears:
He fears that people will be led astray by those on the wrong path, a desire to please the senses or dull the senses with mind numbing activities.
He fears that he won't be taken seriously and his message devalued.
He fears running out of time to complete his mission or watching others suffer.
Motivations:
He needs to be connected to something greater than himself in his pursuit to give and to receive unconditional love.
He must battle his demons to maintain his connection to the Divine.
He must face temptation and hold fast to his beliefs.
If I'm the only one seeing Chantry Sebastian in that, I'll eat my hat. So onwards to the rivalled Sebastian, the King.
King type:
Often has problems filling the emotional void, so fills it with addictions to alcohol, sex and work. (aside: early Sebastian)
He cares about having a Kingdom to rule over.
He cares about having a family, succession.
He cares about being admired and respected for the power and fear that he can instill in others when needed.
He wants to be a strong force to be reckoned with. (aside: Formal alliance with Kirkwall)
He cares deeply about those under his command, and is generous with gifts.
He wants to be the best, and will compete no matter what the cost.
He has a family but will cheat on his wife by flirting or affairs. (aside: Legacy flirt is perhaps a shadow)
He is a consummate politician.
Women see him as a protector
He fears:
Losing his edge, and being overthrown.
He may fear the passion of his emotions, or the lack of his own emotions.
Motivations:
His biggest motivations are his own self-respect and self-esteem.
He'll do anything to remain in power.
He wants to keep the respect of his family.
The negative side of this type is the tyrant or dictator.
Aveline suggests both types in her dialogue. The man who cares that no-one is harmed, and the man who thinks that they would be laying down their lives in a worthy cause.
- Aveline: Has Starkhaven called for it's lost prince, Sebastian? Would you give up if the city has moved on?
- Sebastian: Like Ferelden "moved on" after Cailan?
- Aveline: You've been reading.
If Alistair was made king:
- Sebastian: It's a good tale. King Alistair is particularly inspiring. But I doubt that's how you see me.
Otherwise
- Sebastian: It's a good tale. I'm inspired by the Warden Alistair. But I doubt that's how you see me.
If on rivalry path
- Sebastian: I'm no tyrant, Aveline. If people die restoring my place, they will do so with full knowing. If that doesn't satisfy, so be it.
- Aveline: After your actions here, no it doesn't.
If on friendship path
- Sebastian: I don't intend to let anyone die restoring me to my place, Aveline. The risks are mine. And that will have to satisfy.
- Aveline: It was well said, I give you that. We'll see.
So Sebastian was born into a family where his natural psychological makeup was not right for his actual life. He then turned to addiction (I'm sure Isabela would love the thought of a sex addict).
The Chantry then evolved his personality to become a hybrid type, Messiah often being a hybrid. What happens next is up to Hawke (you).
You confirm the Messiah type - Man of the Cloth
You confirm the King type - Man of the Castle
On not killing Anders, the book that we find in the Chantry has better words than I;
The human heart is more powerful than the greatest weapon, and when wounded, it is capable of the blackest of deeds.
Tales of the Destruction of Thedas.
There is more than that, but really it is all about character arcs. A dictator would find it easy to start a war...