The one the TV Show supernatural posed was pretty genius, it was a combination or "reliving your greatest hits" as in the best moments of your life to essentially a lucid dream.

Everyone's heaven was instanced, and separated from other people (so the friend you might be reliving a memory with, probably wasn't there) HOWEVER a few people like soul mates would have a combined instance, and a few people figured out how to move around instances, one character even claiming he managed to meet Einstein and even in death, he was still a busy guy.

Although the stuck in a loop side of things borders on the terrifying for me, having an instance where I could virtually do anything would be incredibly interesting, however I guess after a while it could get pointless.

My personal idea of heaven is something similar. God knows I've got a lot of questions to ask in if I could find out the answers for myself in my own personal sandbox, that's even better than being told the answer.