I'm leaning heavily toward the swashbuckler (Rogue archetype) simply because I like the versility of the class and the idea of being a witty, urbane sort of character with the fancy moves... and the clothes, of course.

As I mentioned, I don't have a problem with LE, or even NE alignments, they can be fun to play with. If the character gets too much of a head, he or she might find him/herself without much work, but it's just as true for anyone.
I have played with evil aligned characters who seemed to delight in the "evil" part and just do whatever they wanted to screw the party and get themselves ahead. That was my only thought on the matter, and is not a universal trait.
As an example, in one table-top game I played in, our NE thief found out that the party had gotten a bounty on their heads for ruining some evil plot of the arch villian. So, to make himself some gold... he tricked the party into a position of getting captured and collected the bounty on the party... To be fair, once he was paid, he broke the party out again, but tensions between the thief and the rest of the party never recovered.
I usually have two laws of gaming that I ask be observed. The first one is that there be no attempts to hurt or kill a fellow party member. Argue all you want, get into a bitch slapping contest and shoot each other murderous looks, but don't devide the party with open warfare. (Of course, once that party breaks up, this rule doesn't really apply)
The second rule is that theives not steal from fellow party members. I've seen this one kill not just a party, but a gaming group at a table-top game. Just bad business all around.