The sith inquisitor is a weakling who has dumb luck and others plotting for him.
The sith warrior is a wrecking ball who specializes in lightsaber-ing people, monsters, droids, and plots in the face to death.
I much prefer the... direct approach.
The SW is more than just martial might. The way he/she throws people around and insta-snaps necks with a tiny flick makes it obvious that they could rip people apart with the force easily enough, they just prefer not to. It's more satisfying to plunge a saber into an opponents belly.