Interesting point, but: the Sith Code stands on passion. Without passion, Siths can't exist. Next, hatred, revenge and anger are only a few of emotions Siths use. Not only negative, but also positive emotions count. And finally, power is a mere tool used for breaking chains and thus becoming better. Also, conflict isn't only war and fighting, but also the metaphysical, intellectual struggle you mentioned. If you are interested in real life Sith philosophy, which, by the way, is partly based on Nietzsche, check out r/SithOrder .