- Why Supergirl is such an innocent, naive woman and Batgirl is a paranoid asshole? Because neither of their mentors exists, ergo they couldn't benefit from their experience. Superman wasnt there to teach his cousin that evil has many faces -and Luthor can't be trusted-. Batman wasnt there to show Barbara that being too distrustful, paranoid and aggressive is counter-productive.
- Batgirl's Mussolinian/Stalinian management style makes a scary kind of sense when you realize that Gotham's police surely became corrupt like Hell again after the death of the Commissioner Gordon. Faced with the monumental task of saving a city full of criminals, parahuman psychopaths and corrupt cops and politicians, she had to think: "Screw this. I'll do it MY way."
- It's easy disregarding Batgirl's remarks on the Society as her being an ass until you realize Supergirl had previously talked at length about the goodness of Lex Luthor. Barbara -who is pretty cynical and mistrustful- probably assumed that they were also assholes pretending to be decent people.