If you believe Revelation 7, 144000 virgin men go to heaven.
It follows that if you believe babies are destined to go to heaven, since they are the most pure, the best male Jewish babies will go to heaven, and everyone else will be part of the other tiers in heaven, described in Matt 18, which contradicts what I just said:
 At the same time came the disciples unto Jesus, saying, Who is the greatest in the kingdom of heaven?
 And Jesus called a little child unto him, and set him in the midst of them,
 And said, Verily I say unto you, Except ye be converted, and become as little children, ye shall not enter into the kingdom of heaven.
However, atheists have a much harder time dealing with the question, because nothing [beyond this world] written in the Bible is true, we shouldn't take comfort from negating it. That is: just because you can disprove the Christian Hell, does not mean that it is not real.
Atheists have some problem dealing with the physical constants in this universe being so "fine tuned". The logical and scientific conclusion is that we live in a multiverse, in which everything may happen, indefinitely. If everything may happen, then the world is far crueler than any grizzly Christian fantasy. If you take the gnostic approach, that "we" can escape from this world, then anybody/soul that didn't escape, either has to either have another go (reincarnation), or be delayed in some form of confusion, or interminable cosmic wait. The reason that this happens may be nothing to do with how skilled that soul was, but whether it happened to receive certain information (training), which may take an insane amount of time, or not even happen on this planet. In a universe where everything can happen, the concept of justice is only a local phenomena, invented by those who self-implement it.
Consequently, we should not be too theoretically affronted by the injustice of God, but instead, ask for evidence of a particular belief.