I'd argue that the point of the Sith and the Jedi is that both sides are ultimately wrong. The Jedi go too far into the light and turn self-righteous while proclaiming to want to protect everything, a task no single person or even group of people can feasibly accomplish, while the Sith believe power trumps every other thing and that you can only gain power by being a shithead, which is more blatantly wrong but still wrong. That's the whole draw of it for me--not the Force, which is poorly explained in any case and boils down to "space magic", but the moral implications of both the light and the dark side. The way emotions play into both as much as Jedi want to pretend otherwise. The whole thing is intensely fascinating to me.
Plus, when you go back to the origins of both Jedi and Sith, the Jee'dai, you find that they worked in balance with dark and light. You get too self-righteous, you go meditate on your feelings for a while. You get too nasty, you go balance your shit out. And there was none of this 'savior of all' bullshit. Just people with powers trying to figure them out and do the right thing.
Anywho, I'm sure nobody actually wants to listen to me drone on about Star Wars because I could for ages. Tl;dr, Dark Jedi are the only worthwhile force users.
Edit: Also, Episode 8 did the best job of explaining the Force to date IMO. The movie had plenty of problems, all of them Rian Johnson, but some parts were excellent.