What if the system of existence all beings go through is built like a ladder, meaning there is not one, but many phases to pass through before completion? It would stand to reason that since all human beings are born with an innate (albeit vague) moral compass that human life is not the first. What if every phase is about learning to cope with the various issues raised by being born with a subsequently increasing level of clarity to the way you perceive life?
This would make the ultimate purpose of human life to learn to cope with a universe that outright denies our sense of right and wrong, to accept that we, as a species, have little to no understanding of the workings of reality and can do nothing to change it. If by the end of our life we have succeeded in doing so, what would be the primary hurdle for the next plane of reality? What would be the final plane of reality? Would there ever be a "final level"?
If these questions we carry into the end, maybe then heaven is an eternal sense of having something to strive for. Maybe we are already there.

-Al Wright