My durge character was a lawful good Oath of Devotion Paladin 6 / Storm Sorcery Sorcerer 6 multiclass. I stayed within lawful good and never broke my oath throughout the entire playthrough. Usually I don't select lawful good characters and much prefer chaotic good or neutral but here it made sense.
In my mind my character was a great warlord killing in the name of Bhaal before loosing her memory to the tadpole. Her martial skills come from here. While unconscious a powerful deity, perhaps Withers since it's proven he's actually
, reached into her soul giving her a chance to redeem herself by fighting against The Dead Three and spoiling their planned invasion of the Sword Coast hence waking up as a Paladin. Sorcerer side comes from Bhaal.
The story plays out nicely and, as far as I'm concerned, the Dark Urge
IS the canon story of Baldur's Gate 3.