I haven't seen enough of Reyna to see her true character. I mean I can tell she's strong, independent, and cares for her Legion, but I still think I need and want to see more of her.

Piper's just so relatable, cool, calm, and sweet. She's one of my favorite characters.

Piper's character arch was "Save daddy" and "Force myself on Amnesiac" Reyna has a calm, collective warrior that had more practical things on her mind like saving two-hundred godly lives then dressing up pretty like.
I know I am being to harsh on her, like I am to things that are mainstream. (Hunger games horrendous pacing saved by a cool idea that stops being awful due to and interesting situations not the character's or actual writing prowess a cool idea no more. Or Call of duty a repetitious shooter that hasn't being interesting for years and maybe saved by the next one's actual giving a damn)

Some very good points :D
I agree with Spikegilfer about Reyna's thoughts and responsibilities, and I agree with Teddy about not enough character development to judge Reyna's personality and compare it with Piper's. ^.^
I personally like them both equally and therefore find it impossible to participate in this poll! :P

as a character though... i dont like her with jason lol they have like zero chemistry.