She's pretty enough, but seriously, a role like this, given that it will be well written, needs an actress with serious craft who can not only handle the physicality of the role, but also the maturity to handle it emotionally. Diana is going to initially be like an innocent child when she first comes across men, but also as time goes on has to maintain compassion in spite of all that will be thrown at her, and keep looking towards the positive in herself and others so that we can care about her. It's deeper than looking good, being able to say lines, and kicking a little ***. Nobody will care, and it'll end the franchise before it had a chance.