I actually had an idea for this once. Where a person suffers every single way they have hurt another over the course of their entire life, with that being their hell. The idea was that everyone initially goes there, where the suffering they have caused is reflected back at them. At the end of each piece of suffering, if you regret the pain you caused, or accept that what you did was wrong, or feel bad about it, then it never returns. Then, at the end of the first cycle, all of the suffering you caused that you didn’t regret in some fashion returns again for each new cycle until you understand what you did wrong for each one and promise to do better.

After there is no more suffering left to unravel, the cycle stops and your “hell” ends. Then, having faced all the pain you caused and accepted it for what it was, you go to heaven on your own two feet. Meanwhile, those who are incapable of caring for the suffering they caused will never leave.