As an agnostic atheist, I don't feel immoral at all. In fact, I feel like a better person.
I recognize that I don't need the belief in any deities to be a good or moral person.
I don't have to believe in anything if I don't want to, and I can freely form my own
thoughts, and opinions. I am not afraid of what happens in the "next life,"
as I don't know if there is one. So, why waste my life being worried about it?
As both an agnostic and an atheist, I don't feel arrogant at all. I merely don't believe
in the existence of gods, however, this is not something I claim is an absolute 100%
truth, as there is no way of knowing and in my opinion there will never be a way to know.