I do prefer the idea of reincarnation, everything comes in a circle. But human population is increasing, so where is the new numbers come from? There is still much to be discovered.

That is just a thought, I am open to many theories of life after death, but it is hard to determine which one is the "right one", there are no reliable source to this subject matter. Everyone who have been there is unable to say anything about it.
Just live it, and see what happens when the time comes