Religion can be very annoying. I love the Bible. I figure it to be the most anti-religious, pro-freedom book every conceived. It's probably why I'm not embarrased about it.
So this is no different than figuring out by ourselves what rules create a stable society where the happiness of as many people as possible is as high as possible.
I don't really disagree with you. But consider this: why should it be a goal to have a "stable society where the happiness of as many people as possible is as high as possible?" Hint: I know the answer. :-)