The smuggler storyline, which I did lightside, was interesting enough to, well, keep me interested, though the Act III plot twist ticked me off. I'd like to go through it again as a darkside smuggler, but I'm not sure the story by itself could keep me interested because it was pretty 'meh' - average as these things go.
This pissed me off too. Why do they force us to play this way? Plot twists are terrible, and the Smuggler plot twist is poorly executed because they never ever let us query the situation.
I loved playing the Smuggler story up to this point. After this point I cringed my way through it because it was like bile in my mouth.
Sith Warrior is perhaps my favourite storyline so far though
. I play LS and it's really fun. There are parts of it where I would prefer it slightly different, but at least I can develop a unique personality for my Warrior with what I have which I how I like to play my Bioware games
Worst story for me is Imperial Agent. Because it's so boring. I just can't get through Dromund Kaas on an IA at all, I hate being a Sith Lords *****. It's the reason I can't play Inquisitor.