If you were looking for a reply... I'm sorry, I did see the post some time ago but was uncertain of how to respond at the time because this seems more like a personal contemplation rather than a question. Not only that but it's been a long time since I've played and was going through some personal drama at the time. Sorry...
But IF you'd like my advice if you haven't done so already... It's definitely worth saving her. I highly recommend it. At least for now... Still not sure how much the game and story will change for doing so. Probably best to keep 2 save files following separate story lines if it splits off forever...
She is a very powerful ally once brought up and well worth the resources it requires to free her. Not to mention the things she can do for Kara with the spell crafting can make her a very powerful ally indeed. After I got her in the party it made many of the battles a breeze ^_^