The Agent storyline more then anything else made me truly despise the Empire. That level of mental abuse was WAY over the line for me. That was the ultimate betrayal to one of their most loyal citizens.
I don't even agree that it adds anything to the story. No matter how much I wanted to play LS, at that point I felt there was no choice but to go full dark side and kill everything. Anything less felt like condoning this horrible act of mind ****. Every chance I had to take a Light Side option through the whole chapter I ended up thinking "How in the hell can anyone even think of letting monsters like that live?"
Worse yet is how you don't even get to really deal with what happened. You can try to get angry, to yell and scream and demand answers, and all you get is condemning platitudes. If anything everyone seems annoyingly perplexed at why this would upset you. "Oh, I guess sorry you just got literally mind ****d, but no big deal right? moving on..." Apparently it's too much to ask to have anyone actually acknowledge that what happened was really a bad thing. To me it is this fact that everyone is just OK with it that proves the Empire is not worth saving.
What's sad is the Agent could have been he most loyal to the Empire, certainly on my Agent that was the initial intention. Then the Empire went and mind ****ed her and totally tossed that possibility out the airlock. There is no excuse or justification for it.
And yes, the Republic agents who took advantage of it are every bit the hypocritical bastards that people claim they are, but this in no way lets the Empire off the hook.