I contend that any personal decision on an issue is invalid unless it starts with atheism (taken to be defined as lack of belief in anything). Atheism is the logical first step towards discerning truth. Healthy skepticism forces the claimant to provide proof, where one might otherwise be content with subjective experience. Thus, for any issue, atheism is the beginning.
I further contend that the issue of whether God (or gods) exist(s) should also be started from a position of atheism, and that it should end with atheism (now taken to be defined as lack of belief in God -- its original meaning). The claimants -- theists -- have provided nominal, inconsistent 'proof' of their notion. Logic compels us to reject it outright. Agnosticism in this case implies that the claimants have cast reasonable doubt on our skepticism, forcing us to investigate further. They have not. Therefore, anyone who is not an atheist is illogical.