Reptillian
Hamburgler Extraordinaire
Well in my thinking I certainly wasn't considering the existence of a heaven or hell, just existence in this life as we know it (which is possibly all of the existence of human souls that there is). If a heaven can exist, and god does not send certain people, or most people, there, especially for arbitrary reasons, he might as well be the devil, and the whole argument is moot.
I can not see any plausible reason for why it would be necessary for "all sentient beings have to pass through a period of suffering in order to exist in a perfect world."
Its a possibility though, the main point being that without understanding the nature of the program needed to create a thinking entity, we can't really say with confidence that we could simulate a world for them without suffering.