When I played through the first time I just kept on doing mission after mission for the NCR hoping that I would be able to join their ranks (I wore their armor everywhere since I liked the look and it was medium so it served my purpose) and to my dissapointment it pushed me to the end game when I thought I would be offered a job there.
my idea for a future DLC, for those of us who would like to join the NCR... LET US!! I know the gate to the south by the Mohave outpost is locked but can be opened. Why not let us go there, and it leads us somethere we can join the battle against the legion or some other faction that wants to eat our legs, and use our testicles as home decor.
But thats not it!
If bethesda is up to the challenge they can have this flip sides, so if you are a legion supporter, then you do basically the same thing, from the other side. Go visit cesar, he tells you to get your scrawney butt down south, and you fight NCR as you attempt to take over the world *alkward evil laugh*!!
But being able to fight as a soldier would be awesome ^_^
And on the next patch (if there is one) PLEASE make more legion raiding parties. Like when I'm nearby an NCR camp they are attacked by a handful of legion. Or when I happen to be walking by a caravan the legion attack it and I can ignore the fighting, help the caravan or help the legion. And legion ambushes can happen a bit more. I saw in a previous post about if you piss off a certain group they will send assasins after you. Ive pissed the fiends, great kahns, the legion (of course), and the powder gangers to no ends, and they seem to make no effort to kill me off. Either I scared the piss out of them or the developers dont want them to be mad at me.