The Muppets have done a version of A Christmas Carol, and Star Wars is way more popular than even the Muppets, so why don't they make A Star Wars Christmas Carol? I'll bet it would be every bit as good and well-loved as the Star Wars Holiday Special from 1978!
We would open on a still under construction Death Star, and Darth Vader would be killing some lieutenants for failing their missions by crushing their necks with the force or whatever. Then he'd go home, killing anyone he met on the way (because he's evil and stuff). But once home, he would be visited by the red glowing tortured spirit of the evil Emperor, Darth Sidious (who died earlier than he does in the movies {I know, it's a cheat.}), who tells Darth Vader they've been wrong, and he needs to correct his path in life to spare himself the same fate the Emperor is now suffering in Sith hell. And to help him on his path to redemption, Darth Vader will be visited by three spirits: the Spirit of Star Wars Past, the Spirit of Star Wars Present, and the Spirit of Star Wars Yet to Come.
So at 1:00 am, the first spirit arrives, and what do you know, but it's a glowing jedi ghost version of Jar Jar Binks, who shows him scenes from his childhood, and explaining how they got tricked by the evil Emperor, then Senator Palpatine, into giving the government absolute power and joining the dark side, respectively. Then he is shown images of his lovely wife, Queen Amidala, and how they loved each other, to warm his heart.
Then, at 2:00 am, the second spirit arrives in the form of Obi Wan Kenobi, who reminds Darth Vader: "I told you that if you struck me down, I would become more powerful than you could possibly imagine. Now I can invade your dreams as an unkillable nagging force for good." And Obi Wan Kenobi shows Darth Vader how he fought his own son, tortured his own daughter, helped the Empire destroy a whole planet, etc. And then he shows him how, if only he'd been nicer to Obi Wan Kenobi, he wouldn't have had to toss him into that molten lava, and he would still be a complete biological entity, and they would still be friends fighting for justice and stuff.
Then, at 3:00, the third spirit arrives in the form of Yoda, who tells him he still has too much anger in him, and he's going to die alone with the whole Empire dancing on his grave if he doesn't change his ways and become good.
And so, waking up to a new world, um, galactic view on life, Darth Vader becomes a changed bionic man. But once he becomes nice, his cohorts in the Empire notice the change, sense it as weakness and kill him. Then he becomes a glowing jedi ghost himself, and we see him appear in jedi heaven, and then he chases after and beats up the three jedi ghosts who visited him and nagged him into changing his ways, because by making him into a good person again, they ended up getting him killed. The End.