As part of his interview for Empire Magazine in the UK, JJ Abrams revealed a touch more about Kylo Ren of the villains in Star Wars: The Force Awakens. It is assumed that because he wields a light saber and a bad guy then he must be a Sith (the equivalent of Jedi) However, JJ Abrams said "Kylo Ren is not a Sith" who "works under Supreme Leader Snoke, who is a powerful figure on the Dark Side of the Force." Since there are always two (now that the Extended Universe is dead) then he might be suggesting that Kylo is the apprentice to Snoke's Sith Lord or at least a wannabe who is faking it. The character of Snoke has yet to be seen but he will be played by Andy Serkis using motion capture (like Planet of the Apes or Gollum).
As for The First Order which essentially replaced the Empire, is the result of "conversations about what would have happened if the Nazis all went to Argentina but then started working together again" and is not necessarily just ex-Imperial officers. He further teased, "Could The First Order exist as a group that actually admired The Empire? Could the work of The Empire be seen as unfulfilled? And could Vader be a martyr? Could there be a need to see through what didn’t get done?" The idea of Vader being considered a martyr is definitely an interesting concept.