Scion 2E: making antagonists with PC system

[Taevyr]

EDIT: I know the chance's close to nil, but anyone reading this who has a DM in Ghent planning a Scion campaign, DO NOT READ or prepare to be smote. Or whatever the proper conjugation for smite is.

Hello, anyone who's aware of this system and might be able to offer advice.

I'm currently prepping a Scion 2E campaign at the origin level, and it generally seems a pretty straightforward system: aside from the rather messy way the two main books are written, the system is pretty straightforward and I believe I got a decent handle on how to quickly build antagonists, rule skill challenges and the like.

Where I'm having some concerns is using character creation for more prominent villains: I'd love to have a fully fleshed-out 1-legend scion as the main villain of the initial campaign, but have no idea whether that'd be an appropriate challenge, TPK-bait, or barely challenging. I've already statted her out in the basic antagonist system, so I can always fall back on that, but it just feels more fitting to have her as an actual fully-built scion.

Any tips for handling this? Or even the quirks of the system in general, should any come to mind?