I think it's the lack of a clear cut role the hurts Mace the most. While he has no obvious weaknesses, neither does he shine in any area. Which means, in a highly specialized team where every toon has a distinct role, Mace is always eclipsed by someone who can do what he does but a little better. That's a little weird for a character with such profound background in the lore.
Oh, and I don't see the point in calling each other noobs in a thread that's clearly about discussing ideas for developing a character. That's not a smart way to foster a creative atmosphere. And if we want to help create new concepts for Mace, then creativity is a good thing. Just saying.