Hm well, the problem with the Christian version of heaven is that I could not be happy in it and still be me.
If I was to be happy, I'd need all my loved ones, all my friends along with lots of historical figures I'd like to meet.
There should also be a possibility for me to live, for example, in ancient Rome and experience the culture first hand.
And I would want knowledge (that forbidden fruit) of just about all things.
If these things were not to be granted, I would not be happy. unless, of course, God modifies what is me to something that is quite similar, but not quite, me. Then I could let my friends and loved ones be in hell while I was happy for eternity in heaven.
Hm, so heaven for me. Free reign for my thoughts. A free, inquisitive mind able to travel to any situation at any time, soaking up experiences without the taint that we have in life (fear, pain, lazyness and so on). Being in a constant state of amazement of the grandeur of existence, where the discovery of the smallest particle is as great as dive through a galaxy. Knowing, being, feeling, loving. Forever.
Hell for me is not physical pain. Hell is a depression taken to its extreme, without a way to end it. Combine this with a full understanding and realization of the pointlessness of existence. A bleakness radiating, everlasting, never abating, always increasing in intensity. A sense of having reach the limit of what can be tolerated only to face more. And at the same time have FULL knowledge that this will go on, while at the same time being unable to grasp anything worse than what it is in the actual moment *now*. No way out. More to come. Forever.