Do you mean they have some sort of niche and pop out from the background from time to time to offer some unique service? I guess, but why do they need to highlight that on the diagram? Does that make people like Banner unimportant?
That's why I think leadership makes the most sense. It's direct and easy to convey. Highlighting some guy that can teleport leaves me with a "so what" type of feeling. Also, I'm willing to bet that Captain Universe will lead the team she is in. I don't know, we'll see how this goes.