I find your topic very good, however, there is no way to cover, even half of your questions properly within the scope of this thread. So with that in mind, I will limit my response to the beginning.
First off, if you are seeking to scrutinize the creation account with a bible such as the KJV you are going to fall flat on your face. Not because the bible is bad(per say) but rather because of the nature of transcriptions and literary translations. The KJV suffers from some would call timeframe translation issues. In the older Greek and Hebraic texts the implications and weight of the creation account is vastly different from the English translations we have today. Why? because biblical translators had to interpret the meaning of the scriptures in order to communicate the context given from the older writings. This meant that we are in many ways, limited to the translators ability to understanding the meaning of the texts.
The issue for me was that the Creation account simply didn't jive with things. It doesn't take a scientist or a scholar to see that the KJV creation account requires a little contortion in order to pan out with the evidence at hand. However, I was very pleased to hear that the older writings seemed in very good standing with the current state of science on our surroundings.
Since God would transcend time and space, I is not at all surprising to conclude that the earth is old. The universe most likely older since it would seem as though everything is expanding from a single point. I believe that when God said, he created man from earth, that this implied that we came to be what we are today as a result of his will. This would include that out of all the living creatures of the earth, that we are the absolute physical beings above all the living things.
I often ponder whether or not A&E were indeed as we are today. I would think not. How different they would of been from us remains a mystery, however if I had to guess, I would say they were probably completely incompatible with us now. When I think back at the command that God gave Adam and Eve, I can never come to terms with how powerful they would have become here on earth. He essentially told them, do anything you want(make your own world) just don't betray me. He then told them, fill the earth and master it. That command alone, says it all. God was in no way limiting the capacity that mankind would hold as humans. Adam and Eve would have become the parents and recognized authority of all the inhabited earth. They would have been great and likely example of Gods greatness.
There is no mention of other beings other than angels and God while Adam and Eve were in the garden. It is unknown to this day whether they had any offspring prior to there disobedience act. However, had they of had offspring, those children would not of been condemned unless they too would of eaten of the fruit which I believe the account would of mentioned.
I have always considered the Cain and Able account to be literal. As for the soul, The scriptures refer to living creatures as souls which would indicate that Adam respectively had a soul since he was declared alive. I have always concluded that all living people are likewise living souls.
Of all the information recorded in the bible, I never doubted the fall of man. The entire account is far to implicative to discount as anything but literal under the terms.
PS. I have no particular stake against the KJV bibles. I used it as an example since it is a very common and seemingly most used bible when it comes to reading and reference.
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