How about terms like "make-beliefs" or "fables"? Obviously the stories have a message and are very old. A question I often would like to ask theists is wether or not they believe stories like Adam and Eve in a literal, historically correct sense, that a creator literally crafted one man then used his rib to clone a woman. Or if these stories are understood the same way fables are understood, in that Adam and Eve are just symbols for the relativity of all mankind? I can understand that there was a time when these tales were seen as literal truth, but in the modern age I have a hard time believing that so many people truly see them as such. Heaven and hell is another example. Is heaven a physical place where good people live after they die while hell is a physical place where not so nice people live after they die? Or are heaven and hell symbolic states that one creates while he is still living?
You might be surprised at just how many believe the literality of their Religion, and it ain't just Christians. Many people never question the basics of things they were exposed to when very young - it is why so few stray from the Religion of their parents.
Fable is probably a good term; I'd suggest Myth but too many myths are turning out to be true and it might just encourage people to insist THEIR particular myth is true. :D
I doubt a case can be made that Atheism is a Religion, but it is definitely a belief system. Atheists don't just have a blankness, they are sure there is no God. Otherwise they are Agnostics. :D People who don't believe are usually termed Agnostic.
Atheists and Believers are, to me, on the same side of the line. I saw a model a while back on BL suggesting a X rather than a line but I am not sure it is valid. It relies on changing definitions so Atheists can 'not believe' rather than be 'Deny God' which is what the term means.
Atheists who simply 'not believe' in God are called Negative Atheists and very often termed Agnostics.
I think there isn't a lot to like about either Atheism or the Religions, mainly because they tend to see things as black and white. You either agree with them or you're a (insert derogatory term here)
Many Religions see the physical world as an evil place, either a punishment for past sins or a place where demons dwell, and so they tend to ignore things that can be learned here. Mind you, as individuals, many Religious people have contributed quite a bit to our knowledge - perhaps in the beginning the idea that the world must be 'organised' led to the study the world around us?
But Atheists have their own blind spots and so we have a world where anything spiritual or to do with Psi or ESP or events outside the world of Physics get ignored, derided or attacked as junk or fringe Science.