The Jack Sparrow character was damaged in later Pirates films by bad scripting IMO. At times, Sparrow was even made unsympathetic, for some damn reason (his interaction with Bootstrap Bill Turner, who was killed because he stuck up for Sparrow during a mutiny, is especially tone-deaf. I kept waiting for Jack to show some empathy during his meeting with poor old Bill, but the writers pretty much effed it up.) And THEN a line was cut that actually ennobled Jack a bit. He was (as I remember) talking to Captain Beckett aboard his ship, and the subject of "cargo" came up, and Jack was supposed to say: "People ain't cargo, mate." WHY WAS THAT LINE CUT? It would have clearly shown that Jack was against slavery. Jack is a self-serving rascal, to be sure, but giving him a bit more depth sure wouldn't have hurt. And then there were the times when Sparrow was abandoned by scriptwriters altogether to stagger and squint rather than say anything clever or even comprehensible. When his crew is trying to get him to tell them what that key drawing meant, his avoidance of the subject (stagger, squint) was downright annoying. Not funny. Not intriguing. Just annoying.
And hoo boy, "At World's End", what a damn mess of a movie. I was not only let down, I was horrified by so many bad moments. Jack's sniffing nose. The Giant Mossy-Toothed Woman (Calypso). Beckett's dazed Dead Man Walking defeat. And more! Not only was the flick overwritten (way too "plotty", as Howard Ashman would say), it was BADLY written. After the fun of the first two films, the third was even worse than Return of the Jedi (and that's saying something). The only good moment was when Jack stabbed the Heart to save Will and defeat Davey Jones - the distress on Jack's face during that was his only human moment. What a way to wreck a character. I didn't even watch the other films after that one. Decided not to get burned again. Heartbreaking.
Still, I do want more Pirates films...but NOT if they're going to be as bad as most of the films in the prior Pirates franchise. NOT if the Redd character is going to be a soppy Mary Sue, like Elizabeth, who damn near ruined the FIRST Pirates movie due to PC pandering. As for Captain Jack...well, I think he should be in there somewhere. Maybe as a cameo, but an effective one, an endearing one, not one meant to destroy the character, as was done to Han, Leia and Luke in the despicable new Star Wars flicks. Rant over.