Re: Cosmic Centurions
To kind of follow the Green (Red, Yellow, Orange, Blue, Violet, Indigo, Puce, Mauve, Taupe, Cyan, Magenta) Lantern-ish idea, all of the people chosen to wield a ring have a (non-super) ability.
As an example, the people chosen for Green posses the ability to overcome great fear. It's a minor thing (in game terms) but a great weeding out trait.