First of all, good luck and have fun with it - fun is the best part of making a mod.
- You probably know a lot about the planes and fiends already(I couldn't tell which ones are lawful, and which ones are chaotic, myself. I only remember that phrase from the Watcher's Keep: "Tanar'ri! Tanar'ri in the guise of mortals, it is so!"), but I'd still say replay Planescape:Torment with Widescreen mod. Helps to get into the atmosphere.
- It may be just me, but the name has two very strong associations for me: Caoco = Eastern name, possibly Japanese; Caoco = cocoa. The second association is probably a minus. Maybe a strong one. The first one - well, I don't know. But it may add things to her image you're not actually willing to add(anime associations, Kara-Tur associations, Yoshimo associations).
- I'm a little confused on one aspect after reading her backstory: I read that her half-sister helped her with something, and then the heroine wants to punish her father and half-sister? (Also, power for the sake power is a great thing, but usually it helps to have something more specific, so the player would understand and sympathize. For example, Edwin wants to rule Thay, because he's one of the Wizards of Thay, he's kin to a powerful wizard, and that's what all the wizards of Thay want. Is your heroine kin to the lords of her realm? Was she wronged by them? Did she deserve power by birth?)
- Squeamish players. When I read "in her womb" and "fibula", I'm a little squeamish(imagination running wild and so on). You may want to decide early on how explicit on clinical details you want to be and whether you'll want to put a site/Readme warning about it - or whether you need these details discussed in detail, or a light touch would do.
Finally, it's your mod, so you do what pleases you. I'll honestly say that I usually squee more at a certain type of male characters(tall, dark, strong and silent, a chance for a romance or a strong male friend, yep ). But if it's a labor of love, and a well-written one, it will find its audience, like Fade did.