So, i just rewatched the prequel trilogy and had soem thoughts, far removed from my first watching, and also after the new films, The Clone Wars, Rebels etc.

It comes down to this. If you don't buy the Anakin arc, it doesn't matter how good or bad the rest is, it all fails. And for many of us, we don't buy it, for several reasons.

• There is really NO foreshadowing in The Phantom Menace (TPM) that Anakin will turn bad. He's the blonde, ever helpful, committed to others all American good kid. Missing out on putting something in here was insane. Also, relying on the acting talents of a kid this young is rarely going to work out. I think the only thing they tried to do was show he had 'attachments' to peopel which was incompatible with Jedi-ism, but this wasn't greatly effective. It always seemed to clash with the emphasis on connections between peopel Obi-wan talks about in ANH.

• I don't find the relationship between Padme and Anakin believable. I mean, I don't think anyone does. Remember this is basically THE lever for his shift to the dark side. An awful script and terrible acting aside, I don't see how it was ever going to be believable. He had a boyish crush, she is interested in youngsters? There is no development fo their relationship to speak of, he's sold from minute 1 and she doesn't seem to have any journey to falling for him. Maybe he radiates a midichlorian pheromone? I don't see what we are supposed to think drove the relationship, even had the script, acting and direction been on point. And there were so many better ways to do it. Make them the same (ish) age when they met? Then you'd have a teenage crush as an ember they both carried that reignites later. There are many other ways, but it almost seems like they didn't try any of them.

• Anakin's dark side is tied to teenage against not to character traits. He's as emo as Kylo Ren would be later. The greatest danger to the galaxy is teenage hormones and the rage that comes from intractable acne. Again its exacerbated by the acting/dialogue/direction but still. His darkness is all driven by protecting people, but very selectively some people over others. And the other part is his entitlement, that he deserves more, which is really not compatible with the character in TPM. Also, he is selective what barriers he maintains. He never goes back for his mum but he is happy to get jiggy with Padme. If protection of those he loves is his main driver, why didn't this happen in any way between TPM and AotC.

• Anakin's seduction by Palpatine is silly. Its related to the point above. I guess if you don't buy the internal driver for his change, the external one makes little sense either. He preys on the weaknesses he exhibits, but the shift to him believing patent untruths is too abrupt. We aren't shown enough for it to be believable. Had we seen Palpatine messing with the minds fo others more directly, that might have helped, but we didn't get that. Again there were so many other ways to do this. If he'd fooled Anakin into inadvertently doing soemthign really bad, he coudl have then revealed himself and basically said that if Anakin fessed up then it would also hurt those he loved. But no its 'i have a vague idea of maybe stopping an unknown future threat to your weirdly inappropriate wife, pls go kill soem kids, m'kay?'. All we get is some iffy bad dreams, but again with no previous intriduction of Anakin as prophetic, thats not very convincing. Had that, say, been established earlier, it might have worked better. .

• Anakin's change to Darth Vader (suit and all) is too quick. I think they wanted to show the entombing of Anakin, and i get that, but they jumped right to the last stage. Had they shown essentially the v0.5 beta of the suit it might have been much better. Think the hilarious home made spiderman costume in the Toby Mcguire versions, ot the MNk1 iron man suit. It would have given us Vader but left for a sense of time between RotS and ANH.

• [ Added, forgot this before] - Anakin seems nothing like OT Darth Vader. The mannerisms, tone, style and feeling fo the two are hugely different. If you watch the end of RotS then the start of ANH, you get this right away. Again had you had the feeling the metamorphosis took longer it might have worked, but with the presto chango Vader makeover, its more jarring

So there are a gazillion other issues with the films. Some narrative, some continuity, many script, some racial, mostly all summed up as 'George Lucas made ANH accidentally, and peaked at that'. I will list a few in a comment below that occurred to me on this rewatch, but the core is this. The Original Trilogy is the Story of Luke. The prequels are the Story of Anakin. Had this worked better, i think we'd have been able to overlook the rest muuuuch more easily. There were missed opportunities all over the place. Maybe when they reboot the prequels :-D soem of this can be fixed up.