fix-it fic for me is literally just either "holy shit canon really glorified this guy's horrible behavior so I've gotta give their love interest/friends a better ending" (i.e. glee, ofmd, etc.) or it's "i can feel the author's unintentional prejudices/hang-ups/etc. digging their fingernails all over the writing of this character that had so much potential so I've gotta wrest them away and fix some shit" (i.e. doctor who, avengers, once upon a time, the magicians, supernatural, narnia, etc.)