Reading through the thread, I'm still finding it very difficult to find a footing for the argument against the use of this cover.
Did you read:
You know what DOES really bother me about this cover, and a lot of the Killing Joke references?
Joker never shot Batgirl.
He shot a Barbara Gordon who had already retired from the superhero life some time ago.
I think it's a shitty thing to do to put her in the costume and reference TKJ. That's not the Babs he shot. That Babs wouldn't have let it happen. And even if she did the costume represents you as something more than yourself. It is an aegis against your fears as a civilian. If they HAD to make her Batgirl again (they shouldn't have), I would have preferred they explore that idea than the "Oh I must get over this trauma!" bullshit.