Supreme Leader Snoke is an inherently curious character, because The Force Awakens doesn't bother to really give us a whole lot more than "Generic Bad Guy Character" for the sum of its parts. Which is all right, but not particularly interesting. There's no character development in Snoke, and his past - and influence - is kept as a kind of secret. To call him "two-dimensional" would be an insult to a worthwhile geometric model. As a giant hologram man, he's basically Kylo Ren's mysterious boss and the new Emperor Palpatine - albeit of a different species and undetermined height. It would have been more enjoyable for audiences to have at least offered up a bit of an explanation regarding this guy's most basic personality traits, though. It wasn't really enough to suggest he's "powerful" with the Dark Side of the Force. Some hints at his origins, even, or a whiff of his agenda, would have really enhanced his overall menace.