ST TFA does not connect correctly with other Star Wars films

This is taken out of context a lot! The prophecy was misread. That is canon fact!

To have the Jedi and light side take control of the galaxy for so many centuries caused an imbalance in the force. The dark side and light side must be in balance and synchrony. Darth Vader did bring balance to the force by allowing the dark side to rise up and take power before finally collapsing and then being in balance with the light side. So the rise of the dark side was part of the prophecy, until Yoda hinted at the startling idea of the Jedi misreading this ancient prophecy.

Now this balance has been disrupted once again with the rise of the dark side and the force awakens...

 

A prophecy that misread could have been. Mostly by the fans.

It's one of the weirdest things about the Prequels that the Jedi themselves don't know what a "balanced" Force really means, yet they know that they want it. They believe it maybe means defeating the Sith. Which I would tend to agree with - I think that Anakin could have fulfilled the prophecy much more easily and saved everyone a lot of grief if he had lopped off Palpatine's head in his office. I certainly don't agree with the juvenile (and unfortunately widespread) idea that the Force is somehow balanced by having equal numbers of Jedi and Sith, or having evil and good take turns at being in the ascendancy.

Forget canon, because the new moviemakers will interpret the balance thing as they please (if they bother to do so at all). The irony of Lucas commenting that he hopes Disney don't turn the Force into "mumbo-jumbo", when he was the one who came up with this nebulous and unnecessary prophecy.

 

So your argument is that the Sith should be completely exterminated by the Jedi to achieved balance. But in reality, the force will then be in a massive state of imbalance. The dark side and light side must exist together to form a balanced force. And no, there does not need to be equal numbers of Sith and Jedi. The 2 Sith that exist at any one time are enough to balance the force, they encompass the great power of the dark side. The short lived domination of the dark side, was simply the act of rebalancing the force to balanced state.

An analogy for this would be to imagine a car accelerating. Then for it to quickly decelerate, a larger force to the accelerating force must be applied for this to be achieved. Then finally the car will be stationary or travel at a constant pace, this will then be balanced.

To achieve balance there must be further imbalance from the other side before true balance is achieved.

 

Are we honestly getting a complaint that this movie doesn't make sense because it should be a 1000 years later? Lucas wanted it to be about Vader's grandchildren anyways and that wouldn't make sense 1000 years later. They aren't sith, what do you expect Lucas had as the enemy originally? Something entirely different than darkside users?

Your second point doesn't make sense either to me because they didn't mention Anakin, they mention Vader specifically. They're talking about the Vader aspects of his grandfather. You are looking too much into that part, they're merely saying ....the things that made Anakin Vader are the things that are too much in Ben.

So this fits perfectly fine with the series.