I agree that presuppositions are inescapable, but that doesn't mean you can start with any presupposition you want. You don't get to just presuppose that Miley Cyrus is a robot from the future or that the earth's climate is not changing or that the infidel must be murdered. You should as best you're able only presuppose what's shared with others, and try to reason from there.
I don't presuppose there's no god - I reason to it, in basically same way you reason that there are no invisible pink unicorns. (You don't think there are any of those, do you?) And that's also basically the same way I reason that there is no sixth sense of divine revelation - I have no positive evidence for it, plus Ockham's razor.
By the way, thanks for the stimulating discussion. This is a great example of why I love Steemit!
I agree that you can not start with just any presupposition and I did not mean to insinuate that I am a Christian existentialist. I don't believe faith should be a blind "leap" without reasonable basis.
I see a great deal of evidence in the natural world of the God revealed in Scripture: order in the universe, complexity of life, explanation of origin of evil, basis for reality of cause and effect, etc. Then a closer look at the New Testament reveals significant evidence that a group of men and women saw Christ alive after his death and were willing to die for their conviction that he was the son of God.
But before anyone can arrive at that belief they must presuppose that the universe is not a closed system but rather one in which a creator can reach down into and defy known logic (a miracle).