Unitarian services are interesting. I have only gone a couple times with the atheist lesbian neighbors who invited us, and the sermons focused on some utilitarian concepts, power in community, and the goodness in helping others. I did not feel pandered to or prostylytized. Pretty sure if you're looking for a church that is accomodating to atheists, focused on community and good-will over dogma, then you'll find Unitarian services amenable.