A lot of great ones have already been covered, but I don't think these have been mentioned:
Catwoman: I won't share Batman with you!
Batgirl: What? Ewww!
Flash: You're no Captain Cold.
Killer Frost: I outrank him.
Superman: For truth and justice!
Scorpion: There is no justice!
Batgirl: Were you always this slow?
Nightwing: Easy, Babs.
Harley Quinn: Some hero, hitting a lady!
Batman: Do I have to say it?
Superman: You lose, Arthur!
Aquaman: Never to you, Clark!
Batman: I promised Jim I would protect you.
Batgirl: THIS is protection?!
Joker: I liked you better as Robin.
Nightwing: I liked you better at Arkham.
I kind of agree with the suggestion that commentators might consider zipping up during the clash scenes. They are cinematic for a reason. Particularly since we generally get such gems of insight like: "Let's see how much they're going to wager." Or, at best if it is early, "Not sure if I agree with that, it is kind of early."
