So the woman using the sword is what made that not believable?  You were cool with the pirates who stole gold from a cursed chest and became living dead, the random canons on lines to allow escapes, sailing a boat that was completely sunk, and holding an upside down boat underwater,, but the governors daughter learning how to wield a sword ruined the believably of it?  Funny thing is, I really liked that movie, and I still can't remember where she used the sword at some sort of elite level.  I would guess towards the end, but I don't remember.  Maybe I'm just not a great movie fan (as I fully admit, I don't analyze the angle of shots or the setup of the minor plots, I just look to be entertained).  I remember it being brought up about Rey, and I remember thinking "Huh, guess that is kind of true."  I didn't notice it in the least when I watched it, so I doubt I would notice it elsewhere.
Anyways, I for one am not excited for this movie, in large part because I do not think anyone can come close to Williams, and he is the main character I care about in the film.  Smith could prove me wrong, but I'm definitely going to have a bias going into this one (which I think in part was why I hated the Beauty and the Beast remake as well).