I value and resonate with your existential atheism which is closer to the old time atheists of the enlightenment. However monstrous Nature or the Universe is, I think really depends on us, or at least our or, perhaps better, my choice (to take responsibility). Somehow through evolution we/I acquired the ability to keep transcending (through inquiry and behavior) my thoughts and actions. The choice for me is to decide the good and evil of my life, thinking, and acting. To be or not, to inquire or not, to love or not. It’s kinda like Pascal’s wager (tho I think the mathematician was a cop out using game theory—and confusing faith with beliefs, I.e. the ability to transcend with belief in transcendents (beings, places, books, etc). My decision is in the here, now, and with—ie my present—with my past shaped, future desired existence. So right now and I choose for my future to be a happy, optimistic nontheist