I guess extinguishing all life force in the galaxy is one way of becoming the strongest man in the galaxy. Hell, why try to stop him then, the man only want's superior knowledge.
Killing billions of innocents it's not war it's genocide. It doesn't show sigh of strength but of weakness. I don't compare sith with spartans, I compare them with WW2 Nazis.
^^ Absolutely. If one deeply considers it, the Jedi are better. They're not the most perfect group ever. Far from it. They have issues. They can be hypocrites. But as a whole they are infinitely more just and less freedom-suppressing then the Sith.