I'm atheist, but I do not put so much time and effort on atheism
I think that's an important point. I understand why people do it when they live in a super-religious atmosphere, but "atheism" has always seemed to me the assertion of a negative, rather than the assertion of anything positive, and asserting a negative hardly seems like a unifying them. The Epicurean theology gave them a "positive" to assert, along with the rest of the philosophy, as points of like-mindedness between them.