Though is was rather confusing at the time, Scion was basically meant to be Exalted Modern, with a few key differences. The premise was a bit easier to understand than that of Exalted (in that you didn't have to explain the basic setting in a big paragraph that would have served as a Star Wars screen crawl). You get to play the children of gods in the modern times, and do cool John Woo type things or stop buses with your hands.
Basically, a mix of a super hero game with some myth and divinity thrown in. I have not yet looked at the follow up books, but the idea is that you can eventually ascend to godhood. Despite that, I rather like the concept of a lower level hero, as it gives a lot more room and relatability for adventures that can be street to street, like most of White Wolf's classic products. The stories you can tell at this level are human ones, of passion and pathos.
So far, it has been difficult to tell those same stories through a storyteller system without it being rediculous and/or appropriate. I'll reserve my judgement, but so far I am pleased with Scion Hero. Also, bonus points for using the Aztec pantheon. Hardly anyone seems to care about those Mexico gods.
The powers are well scaled, and not as bombastic as Exalted, given that you are still beholden to the constraints of society somewhat, or at least for the time being.
All that being said, this is an amazing book and I almost wish I had given it a second look sooner than now. You can thank my kids and their current infatuation with Percy Jackson for this review.