First, I'm most of the way through chapter 1, so I this may not reflect the whole story. Lightside warrior is a lot less 'let's be nice' and more 'avoid damage.' The lightside options on the Sith Warrior are often more guileful and clever ways of avoiding conflict. You can get through the first mission (I think) of Dromand Kaas without drawing your lightsaber. The way my Warrior works (at least in my head) is that while she puts up a facade of cruelty and bloodthirst, when the chips are down she's actually avoiding bloodshed. She likes fighting, but not killing the helpless. The end result is that you're direct on the surface, but clever and creative with your solutions and more loyal to conscience than the Empire.