I say forget having rules on how to bring Batman back. I mean, did Nolan start his trilogy with a checklist on what he didn't want or did want from the previous films? From my understanding, he went to the source material and pulled from that what he wanted. That's what a new film maker should do. Ignore what previous films did and pull from the source what works for you. Hopefully they'll get someone that wants to have things like Robin and other heroes in this world.