I can stand her being Light-risen because there’s a very specific story that can be told with it. It’s the only story I can see that would change my mind completely to actually enjoying her.
I want her to start using Shadow and have the Shadow effect her the way Light effects regular Undead.
Her sole motivation is serving her people, but the power she wields is caustic to them.
A Forsaken get injured and she instinctually reaches out and heals them, only to be horrified as they scream in agony.
So to better suite them, she respecs from Holy to Disc and works with Aelthalyste to wield the Shadow. But it’s a painful process that threatens to warp her body and mind.
Wielding Light is said to be a self-destructive act for Forsaken, and I’d have it be the same for Calia and the Shadow.
Plus, it lets her get spookier.
Make her model more undead-y and have her mind struggle with the darker emotions the Shadow amplifies.