It's why Batgirl sucks so much.
Don't do the Limbo
I don't think the sales of the previous batgirl book had anything to do with the tone of the current one. I think DC assumed 'character x will sell no matter what we do' with most of the bat-family they kept around. But I would not rule out the possibility of the previous series having an influence. I may be giving DC too much credit, but I think it is entirely possible that they decided that given that the last issue of the previous series came out the month before the first issue of the current one they had to make it different from the previous series so people couldn't directly compare them and say 'why did they have to change the character when they are doing the same thing?' Look at what happened with Smallville, where they gave all of Steph's dialogue and mannerisms to Babs because editorial are a bunch of dumb monkeys. It didn't work, and both Babs fans and Steph fans were pissed off. Even the most insane Babs fan on this board was upset by it because it clearly wasn't Babs speaking or acting even though they called her 'Barbara Gordon.' I think it is entirely possible that DC wanted to avoid that problem on the scale of an ongoing but was ok with it on the smaller scale of a few minor guest appearences in an elseworlds book.
Originally Posted by The Lucky One
It's not just Batgirl or Nightwing but most new 52 are grim stories. Like at Catwoman. Outside of Batman is Wonder Woman or Superman. That why New52 sucks to me. Pre-Crisis and Post Crisis stories at least mixed genres and and not all grim.