Just because the WHOLE of the bible isn't to be take literally and concretely, doesn't mean NONE of it is nor doe sit mean it has NO value.
Lots of great books are not taken AT ALL literally or concretely and they still have great value. If the Bible has to be separated into true parts and embellished and/or allegorical parts then who is qualified to determine which parts are which? And upon what bases are those determinations made?
The Bible is still a good book. It just isn't THE "good book" based on the fact that so much of it is demonstrably WRONG.
That is the type of thinking that drives people to the two extremes of the spectrum - Fundamentalisim and Atheisim.
I would assert that no thinking at all is what drives people to Fundamentalism, but I get your point. But it returns us to the issue: if much of the Bible is factually incorrect, how do we know whether other parts are or are not correct?