Calia had a lot of promise because she was (and still kinda is) a blank slate.
I personally would’ve preferred if they played up her trauma and PTSD from having survived a zombie apocalypse, basically, and suffer from not only doubt in the Light which she feels failed to save her kingdom (and her loved ones) but also doubt in the civility of the new undead she’s come to know as the Forsaken (Faol), with them only ever reminding her of Scourge, just different. Also constantly reminded by her brother’s horrible actions and what it did to Lordaeron and elsewhere.
Then her presence becomes known to the Scarlet Crusade (Brotherhood) who see this as a chance to bring further legitimacy to their cause. Through propaganda and anonymous letters from the Scarlets, she starts to remember what Lordaeron used to be like, filled with nostalgia of what was and her faith in the Light returns. Before Faol is able to guide her further on her path, she abandons him and begins associating with the Scarlets, who hold her in high regard and see her as a chance to restore Lordaeron.
However, Calia is still sympathetic to her people, not just the living but also the undead despite her prejudices and secretly contacts the greater Alliance about making an enclave for living Lordaeron survivors with the plan to have the Forsaken eventually moved elsewhere so that the living would fully return. Her association with the Scarlets concerns the Alliance but they see her as a way to retake Lordaeron so they meet with her personally, etc.
Meanwhile her plans become known to the Scarlets and causes a schism of those who consider her a Forsaken sympathizer (since she doesn’t want them outright killed) and wish to have her interrogated/executed, with some even revealing their doubt all this time in her being the real Calia Menethil. However, some Scarlets are willing to protect “their” queen and see their goals come to fruition, being as desperate as they are, so they vow to protect her, even if it means eventually having to work alongside the “lesser” non-human races of the Alliance or maybe they’d eventually turn on her.
I don’t know, it’s just an idea I thought of a year or so ago. They could’ve taken her in any direction.
Calia as she is, was introduced as a wise, reasonable but boring priestess with no interest in Lordaeron. She’d stupidly get herself killed because wait, she does care about Lordaeron, then after holy reanimation, she’d slide into the Horde’s DMs before just going with the motion, undisturbed by all the things the Forsaken had on display. Morals and beliefs be damned, she’s determined to see these as her people! No connection to what they’ve been through, no connection to their foreign “culture” in contrast to what she’s known all her life. The plot demands she be the Light Queen of the Forsaken, I mean a member on the Forsaken council.
I don’t hate Calia but I am disappointed in her execution.