I think what Legacy needs is a clear mission. Its conflicting priorities make effective leadership impossible because it has no direction. As part PR device and and part combat team, it makes comprimises that hinder it in each area. And it's tendency to split into sub teams and bring in Reserve members for missions prevents the team from developing much teamwork - the people you trained with probably aren't going to be ones covering your back.
Moreover, why assume that Legacy is even intended to have sterling teamwork and effective leadership? I don't think Legacy is meant to have much capacity for autonomous action. The current situation keeps the team fairly dependent on its higher ups - namely Paragon - for direction and dispute resolution. I don't think it was ever stated exactly exactly what, if any, actual authority Mark and Anika are supposed to have over the other members. So that makes their command roles pretty nominal.