The further I go from believing in a God, particularly a personal God, the higher my self-esteme becomes. I find that I can look at the world with a much greater sense of wonder and I'm so much more open to learning new ideas and thinking about new possiblities!
I've found it so liberating to be free from the idea of God and divine reward and punishment. I'm not terrifed of Armageddon or hell anymore and I've been really motivated to get out there and actually start actively helping people by volunteering at various charities.
I'm not constantly scared and guilty because of my own thoughts and my own body. I don't judge people for their personal lives anywhere near as much either.
That said, it's not up to Atheism to coddle and make comforting promises to people. That's what religion does. Lots of things that aren't true can be comforting to believe in over the actual truth and maybe some people would prefer a life of ignorate bliss. But for me, I'm sleeping a lot better at night without the idea of a tyranical God watching and judging my (and every other person in the world's) every move and every thought.
Atheism doesn't say what you can believe anyway, only that you don't believe in a God - It's an absence of belief. From there you are a blank sheet of paper and can go on to think and believe whatever you want. Humanism Philosophy, Buddism, Taoism... even Aliens and that weird New Age Spirituality jazz!