Honestly, I don't think the JLA is a team anyone can really lead. It's supposed to be the best of the best of superheroes, who are a very individualistic bunch. Look at the times that the League was at it's best. Could you really point to who was the leader? Who led Morrison's League? Who led the satelite League? The Chairman was more along the lines of the poor sap who got saddled with making sure Green Arrow and Hawkman didn't get into a fistfight at meetings. A group like the League is incompatible with leadership the way Robin (Dick or Tim) led the Titans, or the way Oracle led the Birds.