It probably does make too much sense, but I've always been of the opinion that even a "mindless action flick" should at its heart still have something resembling a coherent or intelligent premise. It doesn't have to be the main plot point or anything. Just something that comes up somewhere, maybe for the big dramatic bit 2/3 of the way through like there always is.
The Empire is gone and that was the central conflict of the OT, so I started thinking about where to go next. The other thing that pretty much defines Star Wars is The Force, so that has to come into play. With this "next generation" thing and Luke passing it down, I thought about Luke's own training, and remembered that it always bugged me how little training he got, relatively speaking. Then I thought about Anakin. He was like nine years old and The Jedi Council said he was too old to train (which was stupid and basically just a plot device, but still). So Luke came to it really late, but learned from the Jedi Master. What kind of abilities will his kids have?
Or more likely, Han and Leia's kids, which of course would also be grandchildren of Anakin Skywalker. Leia was a rebel, Han was a badass rebel, what would their kids be like, and what kind of issues would there be in raising them, and training them in The Force?