I read that George Lucas' vision for Episode VII was very different from the movie that's been breaking records ever since its December 18th release--and that he's not at all happy with Disney's version. I don't know if that's true; I don't know if his version would have been as popular as The Force Awakens. But the suggestion that he wanted to go with all new characters, "no retro," makes me think I couldn't have liked it as much as I like J.J. Abrams' vision for the franchise. I'm glad that Han Solo, Leia Organa and Luke Skywalker returned to maintain the continuity of the franchise. I like knowing what happened to them after the credits began to roll on Return of the Jedi. I love that the new characters are connected to the old ones. The writing is far superior to the original movies, and the special effects take a back seat to character and action.
The Force Awakens borrows heavily from the plot points of the original. There's a new and (unfortunately for the Resistance--formerly known as the Rebel Alliance) improved Death Star, now known as the Starkiller Base. (Clever--George Lucas had named Luke Skywalker Luke Starkiller in an early draft of A New Hope, I hear.) The Galactic Empire is now the First Order. There's even a Darth Vader wannabe--not a menacing Sith apprentice like Darth Maul in The Phantom Menace, but an immature, whiny brat calling himself Kylo Ren (Adam Driver), leader of the Knights of Ren. He's set out to "finish" what Darth Vader started, but as he's told quite bluntly in one scene, he'll never measure up to Lord Vader. Even if he does have conversations with Vader's burned out helmet.
Yes, I know Anakin Skywalker was also a whiny brat. So, to a degree, was Luke Skywalker--whiny, but not a brat. But couldn't whininess skip a generation or two? It would be a refreshing change. It would also make Kylo Ren a more convincing bad guy. Especially given his lineage, which is revealed early in the movie.
This film is a perfect balance of the old and the new, character-wise. There's a hotshot pilot named Poe Dameron (Oscar Issac) and a young scavenger, Rey (Daisy Ridley) who has powers she can't understand--yet. Abandoned on Jakku as a child, she refuses to leave, certain her parents will return for her someday.
There's also a Stormtrooper who was taken from his family at an early age by the First Order and trained to serve without question. He doesn't have a name, only a number--until an attack of conscience leads him to free a captured Poe Dameron. Together, they escape and Poe refuses to address him by a number, dubbing him "Finn" (John Boyega). Separated in the crash of their hijacked TIE fighter, Finn encounters Rey--and the Millennium Falcon, abandoned in a junkyard. As they attempt to escape the planet Jakku (which looks an awful lot like Anakin Skywalker's home planet, Tattooine), they're captured--by someone who's been searching for the Falcon for a long time.
Harrison Ford and Carrie Fisher, as Han Solo and Princess Leia--now General Organa--have both aged well, but play their characters as battle-weary and forlorn, having dealt with a lot, good and bad, in the decades since we last saw them. Leia is searching for her brother, Luke, believing only he can restore balance to the Force and help defeat the First Order. She's also looking for the child she lost, the only child born of her union with Han.
Standing in for Emperor Palpatine is a character called Snoke (Andy Serkis), who only appears as a hologram. That's one ugly dude--he makes Palpatine look almost cute. And while R2-D2 and C3PO do appear in the movie, the droid spotlight is now on the plucky little BB8, a rotating droid who carries the last piece to a puzzle both the Resistance and the First Order want: a map to the location of Jedi Master Luke Skywalker, who went into a self-imposed exile after one of his students was lost to the Dark Side and...well, if you want to know the rest, you'll have to see the movie. I've found most people tend to get nasty when faced with spoilers!