I started as Republic. I actually like the good guys in Star Wars. I like my evil to have meaning, purpose, and that can't only be "we will rule the galaxy" like the Empire is. I was happy with my Trooper. He was heroic. He was courageous, he was loyal and he would stand against the armies of the evil Empire until we were victorious or he draws his last breath. He was aware that the Republic is not free from corruption or evil doers, but that was a way tamer fate than letting the galaxy be controlled by the Sith.
Everything changed when his world (server) started growing empty by the day. The poor commander didn't have an army of brothers anymore. Didn't have people to stand with against the Empire, who also seemed like they were strugling with the same problem. Maybe the war was coming to and end? The commander became depressed and just stopped showing up for work.
But new life came to be on another world ruled by one known as The Fatman. A world filled with people and possibilities where a young Bounty Hunter found her purpose in the world. She works within the Empire, doing their deeds to gain trust, but secretively frustrating some of their plans and feeding information to the veteran Commander, so that one day they may deal the decisive blow to the Sith. She's an Imperial at sight, but a Republic ally at heart.
TL'DR: I love Republic, don't like Empire. But when my server became empty I was forced to switch, so I decided to play the other class I wanted to the most: Bounty Hunter, even though I had to be Imp to play as one. But I kinda imagine her as a spy or something like that. I work for the Empire, but I'm not one, and I made her an ally to my Trooper through Legacy.