Well, the original character wasn't a resident of Eberron, and so I think that in transporting her to that setting, they may see her as an embodiment of the Silver Flame, especially if she tends toward Good more than evil or chaos. It also offers an added character hook which I hadn't considered, which will help me tie her into the Eberron setting even more. Score!
As for the power level of the class, it's basically pretty good melee damage a-la your typical blaster. It gets access to a small variety of other tricks thanks to having some limited access to other circles (like spell descriptors/subschools, or martial disciplines).
I think that anything that may seem too powerful would be easy to scale back if needed, though I doubt it'll be largely necessary. As for race, the original character was a Lesser Aasimar, but in the interest of not relying on sourcebooks from other campaign settings, I may simply stick with Human for the bonus skill points and feat, rather than just trying to squeeze every last bit of ability score by scouring race lists and just shoehorning it into the character. That extra feat can certainly come in handy regardless, and humans can exist pretty much anywhere in the campaign so that's another benefit, fluff-wise.