Alignment Restrictions: No LG or CE strikes me as random and a touch arbitrary. Might want to call the class "Force Adept" or something more generic because "Sith" carries with it a lot of assumed information. No idea why CE would be excluded either way. "The structure of the dark side" doesn't make much sense, and just isn't a thing. The Dark Side is about passion and emotion. The fluff descriptions in general seem to be a mix of the Sith race, Sith organization, and Sith as dark side users.
I wanted to make a sith, but it dwindled and dwindled until really only the name remained... changing.
You also need to be more specific about what bonuses/whatnot carry over when you make a Light-longspear or Light-spiked chain.
I did. I said its all the same save for things such as reach. Their already sorta considered small weapons, as its just a hilt until you activate them. But things like pull arms or spiked chains, whips. They could all make nice Light- things. Making trip attempts doesn't make much sense with a thing of energy. So asside from cool factor, Light-Scythes won't be very beneficial...
Maneuvers: The discipline choices seem ok. Stone Dragon sticks out the most from a "sith" theme. Biggest concern? The recover mechanic. Might as well not have one. A free action 1/round? That means you are never, ever down a maneuver. You never need to make a choice as to what to use. Used a maneuver this round? Just recover it afterward. Need a different one? Switch it out for free. This is the best recover mechanic, like, ever.