For me it is the Paladin Quests...

Hear me out...

The first arc, through A Realm Reborn is about redemption of a Knight's reputation. The greatest Knight, rumored fallen, chooses the PC to carry their soulstone.

The current head of the Paladins feels betrayed by his former mentor. He is all but consumed by it. So blinded is he, that the mere insinuation that the PC was working with the so-called fallen Knight that he betrays you. Which is a betrayal of a knight that he mentored.

His dishonor is cleared by the voice of his mentor returned and the true corruption within the order expunged

It is a classic redemption arc.

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The Heavensward's arc is about empowering a new Knight. He, and you, seek out a thought dead knight's gear. Finding clues as you do, to recover a sword.

It is revealed though, that it was but a test. In a legitimate twist the character this was all about, a young Paladin isn'tthe chosen one, but he is no less a Knight. While the PC relinquishes the blade, thought rightly chosen by it, because as a true Paladin they seek not power.

Sadly this is as far as I've gotten.