Start as a official Recruit at Camp McCarren or so, and in the end be a Colonel.
Why can't I be a Legionnaire Recruit, do some basic training, officially get their clothes and a Machete for a start, and after many quests and fighting, be a legit Decanus or even Centurion in the end fight? Why can't you actually join any group? Yes, you get a high rep with a group, you can wear their clothes, but you are never really a part of them, even in the end fight.
