A lot of the canon support the idea that "Balance" simply means the absence of the Dark Side.
However, the Gray Jedi represent more of a balance, than the Light/Dark dichotomy:
“There can be no chaos without order, no good without evil. Such is the way of the universe. The Force flows through us all, in all of its peace and passion. This, the Gray Jedi believe, and by this, we shall live…”
They (generally) do not associate with the Council, or the Empire, and simply follow the idea that all aspects of the Force should be mastered, regardless of their apparent morality.
The latest movies, however, seem to be leading more toward an absence of all Force users, all together. Luke wants to abandon the way of the Jedi, and tries to teach this to Rey, though potentially sees her as a way to end it all - she has power, and seems to have an aversion to the idea of the "Jedi" - in that she only wants to control the power she has, not necessarily use it for good, or evil.
This is only speculation, at this point, until the movie is released.
Ultimately, those that talk about "Balance in the Force", depends really on who is saying it. Some talk about Light without Dark, some talk about control over both, and some talk about the absence of all of it.