Good post, losthobbit. 'Customized religion' describes my journey quite well. After leaving the Witnesses in my teens I rejected religion altogether, and called myself an agnostic. But religion remained an academic interest, and the more I read, I found that there was a whole world beyond theistic debates. Reading about the religions of the east was a real eye opener. Taoism and Buddhism remain the two traditions I most identify with. I have attended a Buddhist temple, and found the experience to be positive. Debate was allowed and even encouraged, and one did not have to self identify as a 'Buddhist' to be involved. Quite a departure from the religion of my youth.
I have also read some books by the mythologist Joseph Campbell, which caused me to think of religion and spirituality in a different way. Instead of getting bogged down in literalism and what 'really happened', I began to look at religious stories as poetic metaphors for deep existential 'truths'.
Most recently, I've began to read the Bible in this poetic way, and now find it a pretty enriching book. Stories that I thought were strange when taken literally now take on a new dimension. For instance, Jacob wrestling God is a metaphor for how we all grapple with difficult existential questions. I don't feel the need to identify as a 'Christian' or believe in concepts such as original sin to take value from some of the stories in the Bible.
So yeah, I have a belief system that's probably a hybrid of eastern thought, poetic reading of mythology, and insights into evolutionary psychology. I don't feel the 'need' for this religion, it's just a natural byproduct of exploration.