There is also the shaky ethics of someone taking up the mantle of Fate since Nabu is basically holding them hostage. What kind of person would want that responsibility? Would it be right for her to train someone else for the role just so she can reunite with her father but rob someone else from having a normal life? Plus Fate is probably a necessary evil in order to keep the bad guys in check so its not like you can just kill him either.
Do let us know what you think of the show.