well, in SWTOR generally people divide into those who play for mechanics and those who play for role/specs. I would not, ever turn from Juggernaut simply because holding saber 2h is much more effective than using dual sabers in combat. 2h way is much more stable and safe.
You seem to have forgotten your own category : the ones who plays for a visual style. (I'm myself one of them)
Choosing a class on what they wear/use is not in the domain of mechanics, and neither in the domain of role/specs.
I think that in SWTOR we can add another category that doesn't exist in other MMOs : the ones who plays for an image/story.