I want to jump in here and make a point. I hear you on the side of getting rid of a literal understanding, which doesn't add up rationally, of course, and seeing that these are metaphors, which I certainly agree with. But I want to point something out to provoke some thought. Things, or truths stated in metaphors are not "mere" metaphors. Metaphors can be and most often are far more powerful than facts. Myth and metaphor speak volumes of truths in a symbol set, whereas mere data collection lays flat and sterile.
Bear this in mind as I illustrate further.
If someone looks at the Garden of Eden story as metaphor, what is it saying? Reject the idea it's speaking of some scientific reality of we are in these "sin states", that Jesus' blood changes at some magical molecular level which changes us into "saved state" conditions. This is silliness, but is in fact how someone has to somewhat imagine this when the symbols are taken as facts. This is the trap of the literalist mind, which cannot grasp metaphor and either "believes" or "rejects" based on this mode of reasoning.
So the metaphor then, to stand back from the literalist mind, what is it saying? It can be understood in many ways, as that is really the point of myth and metaphor which is to provoke the discovery of truths in themselves through one looking through the lens of them. Here's a way I hear and understand the Genesis myth. It speaks through metaphor of the existential condition of the individual feeling separate in himself from the world and from others. It speaks of this state of separateness and the desire for unity. It paints this self-realization in a story of a fall from paradise, a separation from that state of desired unity, and it does so through story characters. Adam and Eve were one in bliss, with each other, and with the whole of the natural world, living in the light of spiritual knowledge. That's a beautiful metaphor.
And so then "something happened", to get us to where we are now, longing for that return. The story unfolds symbolically and we have us ending up in a state of where we are today, seeking a path of return to paradise, a return to unity. All the rest are ways to describe this human experience, of our hopes and dreams, and despairs and dreads. If you read these things with an eye towards that, then you understand them as they really are applicable. They speak of timeless, human truths through relative symbols and signs.
This is a shift in that mode of thinking I was talking about. Shifting from a literalist struggle with myth and metaphor in a rationalist framework. Once that's done, then all these stories from all the world religions begin to make a bit more sense, speaking certain truths, in certain contexts. The truth of them, is not from outside yourself in the texts, but what is heard and takes shape does so in the context of the individual themselves.
Here's something I always love to share because it speaks so well. I hope you find it helpful:
Biblical Literalism