The Ken Hamm type of logic is bewildering. They have to believe in a "literal" new earth creation because that's how they created their dogmatic logic; otherwise, the foundation of their faith falls apart. When seeking truth, it's much more elegant to leave room for what we don't know. If the originator of all things wanted us to know all the creation facts in perfect detail, he would have left us more obvious clues. But he didn't.
I wasn't there when the universe sprung into existence, so why be dogmatic about the details? And like you say, we should view the creation stories for what they are: Symbolic stories that explain creation and the origin of our universe from the perspective of ancient people. Of course, the ancients knew less about how the universe formed than we do. But these civilizations worldwide still found ways to record and communicate archetypal creation accounts because they had the same question we do.
That said, we do exist, somehow. And a universe that "self-generates" itself out of literally nothing, with zero intelligence behind it, requires at least the same leap of faith as the new creationists have. So the question remains; How did we come to exist?