Okay, so the books are a bit vague about these it feels (or I'm just not getting it).

During character creation your Duty/Obligation stars at an amount determined by group size (let's say 2pcs so we start at 20). But that means that you can only choose essentially the top 2 or 3 options (example from AoR: Victory, Intelligence, and Counter Intelligence) because those are the only ones that have a number next to the 20 or lower. But it also gives the option to roll for Duty which has roughly an 80% chance of landing on a Duty out of your point range (and if you roll 00 you even get two Duties likely to be way over your 20 starting score.

What am I missing?

Also, all of the Duty/Obligations are written assuming you're anti-Empire. Is it impossible to start this game as a Seth or Imperial Officer (perhaps on his way to becoming disenfranchised with the Empire and defecting but at the beginning of the game still a member of the Empire)?