I’m an agnostic atheist myself, and I agree there are plenty of harmful effects religion has caused throughout history; but, negativity aside, how do you believe religion has helped humanity? So often we get caught up bashing religion, perhaps we do not always consider the benefits.
Since you qualified your question, I think I can say this: The biggest benefit I can think of personally receiving from religion was community and learning about networking. I consider those to be very important skills that I automatically take with me. Group singing is another thing I loved about religion.
I believe if it weren’t for religion, humans would find something else to fill this need for community and group chanting or singing. In fact, some argue that sports does this.