Exotics should be god-tier. They should also be extremely rare. It's what you pull out when something really nasty needs to be put down. And I realize I'm about to put myself out in the cold but, exotics should not be usable in the crucible. If you want exotics to be worth being rare then they can't be included in the pvp meta. If you want to use exotics in pvp then they have to be balanced against the other weapons.