ST Do Dark Siders necessarily need to be Sith?

So thinking about potential villains in the ST and the reading retcons thread got me thinking... in the Star Wars universe is anyone who uses the Dark Side of the Force considered a Sith or are the Sith a tribe or cult of Dark Siders.

I have always felt the Sith were more of a cult of of the Dark Side and not representative of the Dark Side as a whole. Thus by Anakin destroying the Sith, he did not destroy the Dark Side, just the Sith.

So I ask this, depending on what your interpretation of the Dark Side is, will the filmmakers rely on the Sith again, or introduce us to another sect of Dark Siders?

Mav Edit: I do believe this topic could be discussed in the below linked thread.

 

http://boards.theforce.net/threads/...ith-should-be-explored-in-episode-7.50014634/