I blame @luckyjak - not for any particular reason, but it seems like a good idea.
Anakin should never have been Vader.
Anakin falls to the dark side, sure - he’s full of pride and fear, which makes him easy to manipulate, but he is overall driven by love. Not love of power or love of country or any other large, idealistic love, but love of specific, and few, people.
His love of his mother drives him to vengeance, his love of Obi-wan drives him to deception, his love of Padme and their unborn children drive him to hubris. All these things make him easy to manipulate, make him easy to turn.
Too easy, really. So easy, in fact, that he fails on what is essentially his first mission as a sith - he ends up broken, on fire, and abandoned. His wife dead at his hand, his brother turned from him, and everything good in his life ripped asunder by his own doing.
“I loved you Anakin” is the last thing he hears - but Obi-wan can’t kill him. Instead of leaving him to die on the shores, he should have brought him back - if not to save him, then to at least to make him answer for his crimes. Obi-wan’s greatest strength was always his belief in others; surely justice could have been found.
He brings Anakin back to the ship, where he lays in a hospital bed and watches Padme die - not of a broken heart, but because you can’t get the shit kicked out of you followed by a hard childbirth with twins and not have your body say “Fuck you” - and this is where he dies, of a broken heart. Anakin, ultimately, is weak; far weaker than the Jedi, who gain a brittle strength from ignoring their feelings, and light--years below that of Padme, whose strength comes from embracing and accepting and using her emotions to get what she wants and what she needs. His last act is to implore Ben to take the kids, to hide them away from the Empire.
Obi-wan buries his family that day in simple stone cairns, and leaves into self-imposed exile to fill their dying wishes.
And that’s when Palpatine comes into the picture. He ignores Anakin - a useful pawn, but ultimately a failed experiment. No, what he needs is someone like him - sneaky, conniving, strong enough to do what is needed without worrying overmuch about the “rules” that dictate what they can do, but still able to operate in that society without arising suspicion.
And, moreover, he needs control.
In a universe with midichlorians and cloning technology, where the supreme ruler now suddenly has a large amount of corpses from which to gather and use said midichlorians, the Emperor comes for his new apprentice.
Padme still gets the name, and the suit - though now, the suit not only keeps her battered body alive, but also provides the reservoir of power. This is why Vader rarely does more than choke an upstart lieutenant or general - it’s been 20 years, and the midichlorian tanks are running out. Vader is still evil supreme, but now is colder, more calculating, and completely dependent on the Emperor not only for her life, but also her powers.