Prior to the prequils, I always envisioned Anakin as a thirty something, with a great deal of intelligence and presence. That's something that should have been apparent prior to him becoming Vader. The tragedy of him being lured to the dark side being that he had so much more potential, but ultimately was drawn by power and vengance. Instead, we get a whiny little brat played by one of the most annoying actors I can think of. I'd dare say, the dark side actually improved that characters demeanor. At least he quit whining, and pissing about and focused on something. The dark side was the best thing to ever happen to Anakin Skywalker. He ceased being Anakin, and became Darth Vader, and thank God for it.
Anakin should never have been portrayed as a self-absorbed , immature twit. He should have been mature, wise and intelligent, and a generally good man. Show he has a good heart, and a desire to learn and grow. The prequel Anakin never did seem like a good man, so I never felt the tragedy of his passing to the dark side. It was an awkwardly good fit for him really. However, if it had been like Lord of the Rings, with the dark side being the one ring, he could have morphed philosophically over the prequels, giving in to the power, and doing Vader like things throughout.
There would have been no need for the child stage in the phantom menace. He could have been discovered as a young man with a very unusually strong connection to the force.
He had to be trained despite Jedi rules, due to the strength of this connection lest he never learn to control it. In some ways, you get the impression the council almost fears not to train him, sensing there's something wrong. Vader could be why Yoda didn't want to train Luke at such an age. No metachlorines or "the one" crap.
In time, he comes to realize he is stronger than everyone else, changing from a humble and pious man to a power hungry and over confident one who would wonder why shouldn't he wield his power however he likes. He has the prowess and poise to control it (not the sense of entitlement we get from the movie version of Anakin), or so he thinks.
Remove the uncomfortable romance of Anakin and Padme, and redo it with someone in his life from before he was discovered, and have the Emperor use these tendencies towards want of power (similar to Keanu Reeves and his wife's relationship in Devils Advocate) to draw him to the dark side against her. The last movie Anakin betrays the council and Obi Wan, drawing more from the real 3rd movie than any of the others.
Notice the themes and general story remain the same, but the tone of the character changes. And, thus the viewer can understand the tragedy the OT movies imply. A truly good man becomes corrupt and evil. The prequel Anakin we got, was clearly going dark side even if you didn't see the OT movies. He was flat made for it, literally.
