A lot of atheists, famously among them, Richard Dawkins and Christopher Hitchens, deride and criticize religion as an irrelevant and often damaging institution. I believe these guys are wrong.
I think that religion, has a positive and meaningful role to play in humanity. Religion can serve as a moderating influence. Like most things, taken in moderation, it can improve the quality of life. It can promote a sense of belonging and discipline creating a stronger society. It mitigates grief in times of loss of loved ones.
To be fair, the utility of religious teachings is only as good as the credulity of the adherent. This credulity tends to lessen the more intellectually sophisticated a society becomes.
Therefore the real problem with current mainstream religions is not the concept of religion itself, but rather their pace of evolution or lack thereof.
Historically, religious teachings have changed in tandem with contemporary knowledge. One could even argue that during some epochs, religious teachings were a step ahead.
For some reason, the pace of change has ground to a halt as religions became bigger. Today, most mainstream religions are based on beliefs informed by ideas from a time when people were relatively ignorant.
This fact tends to make a lot of the religious teachings seem(or indeed actually be) ignorant. Even though they may have been cutting edge in the neolithic and earlier periods.