My biggest problem (though I really enjoyed the movie) was that the whole time Jack was just drunk. He was not at all heroic. He didn't do anything that made him seem important. He just sat their the whole movie luckily escaping bad situations. He watched as others did heroic things. In EVERY other POTC movie Jack does something heroic or important.
1. The Curse of the Black Pearl: Shoots Barbossa after an epic fight.
2. Dead Man's Chest: Gives up his life to the Kraken
3. At World's End: Stabs Davy Jones (resulting in Will Turners coming back to life as the Captain of the Dutchman)
4. On Stranger Tides: Saves Barbossa and himself from the Spanish camp/Saves Angelica while killing Blackbeard.
5. Dead Men Tell No Tales: ?