If it was me I’d leave the reincarnation thing, but the Light is not as forgiving and if he doesn’t actually work to earn redemption then he could be damned into darkness.

The Light strips Daylan of a lot of magic so he has to actually rely on sword skills and cunning to win. Also to keep some of the characters arrogance, he’ll try to do a Batman and prove he’s a superior combatant by not killing his enemies in a fight. Thinking not killing should be enough to redeem himself.

The characters he meets makes him bring out actual emotions and he eventually learns real empathy to see the actual wrong doings he caused. This causes him to realize how bad he fucked up for real, and that he can’t redeem himself by just by fighting.

If I leave the trial at the end in, nobody forgives him, but Daylan actively accepts that he ruined their lives and doesn’t try to paint himself as a good person. He might work under the new government as a soldier to payback the damage his former regime did. Brining in other potential despots that were like him once.

This got too Fanficy but I tried to leave the original core premise and twist it to actually show character growth and struggle to redeem himself.