They are organized, but that's it. There will be a lot of people pointing out flaws in Legion but my main gripe is that Caesar has no legacy. He has centered all power to himself and himself only. When Caesar dies, so does the Legion. There are no other candidates. Lanius is a soldier and doesn't care about politics. Lucius is probably as old as Caesar is. Vulpes is a small tactics leader, and an agent who most likely has no skill in governing. Everyone else - pure soldiers. Like many point out Legion does not follow Caesar's ideals, they are following Caesar himself. And Caesar is not going to live forever.
And note that there will not be a day when Legion "tones down death a little", "gives slaves and women rights" because that's what's the whole point of Legion, that's what makes it so united. In a Legion society it svcks to live unless you're in the top hierarchy.
The Legion is a good short term policeman, but is it really worth it? Is trading all freedom to security a good trade, assuming you're one of the few lucky ones not enslaved?
Furthermore, Caesar's Legion resembles Ancient Rome in name only. Think if you renamed Legion "Nasty Band", Caesar "Billy", and removed the Latin terms. Where did all the Rome go and who are all these slaver/raiders?