More likely the Abrahamic faiths will get a significant boost in membership. Feel free to correct me if I'm wrong, but there aren't exactly that many religions out there that promise as good a deal as heaven is supposed to be.
People who would convert because of the benefits package are exactly the sort of people who wouldn't qualify to pass the Pearly Gates. You only get in if you truly believe and truly accept J.C. as your saviour, anything less and it's straight to infinite torture forever for you.
Even absent all the possibly questionable Hellraiser stuff regarding how angels act and so on (which I can't comment on one way or another given that I haven't read them myself) I'd call Heaven a bunch of bastards for that alone.
Besides, you want people like the Joker to go to heaven?
Yes. Infinite torture forever is unthinkably evil. No one deserves that. No one could possibly deserve that. A being as evil as Sauron multiplied by Cruella deVille to the power of those jackasses who park in handicapped spots illegally wouldn't deserve that.
If the options are "Joker goes to Heaven" and "Joker goes to Hell" then the only possible moral choice is the former. Finite crimes cannot merit infinite punishment and torture is always wrong.