She's definitely got the acting chops and, at 5'11", she's tall.
But I think the best thing for the show is that she's not enough of a known quantity (despite a prominent role on Friday Night Lights and a number of roles on genre fare like Supernatural and Smallville) to come with a lot of baggage that will get in the way of the work she'll be doing.
That said, I'm with Alyssa and Alan Sepinwall that the David E. Kelley-produced show sounds really fuckin terrible*. The show sounds like Ally McBeal with superpowers, which I bet is how the pitch went too. Because I genuinely think David E. Kelley is a man with exactly one idea.