Octavia156 said:
1. Abraham was a Sumarian. Most of Genesis is a reshuffling of Sumerian Mythos, most of the names are borrowed.
Actually, Abraham would have lived in the time of Old Babylonian period, probably between 19th and 18th century BCE, when Sumerian as a spoken language had died out, though the Sumerian writing system persisted to at least 15th or 14th century BCE.
I doubt very much Abraham lived in the 3rd millennium BCE, even if he did exist. And Abraham didn't exist in any literature until the Torah were written (which includes the books of Genesis, Exodus, Numbers and Leviticus), probably in 10th century BCE or later still.
Octavia156 said:
2. The Flood described on the tablets is one of historical description - they were written over 5000yrs ago, but they were telling of a then ancient time past.
The Sumerian writings have indeed existed 5000 years ago, however, there were no writing about the Flood 5000 years ago. The writing system was not developed enough for writing literature prior to 2500 BCE (4500 years ago). Oral tradition may have been more developed, but not the writing system. The Eridu Genesis (a name given by modern scholars to the Sumerian clay tablets that were found), which is the name of the oldest extant fragment that we have about the Flood is no older than 23rd or 22nd century BCE. The Sumerian poem of Gilgamesh (The Death of Gilgames) do mention this Ziusudra.
Here, this Flood hero was called Ziusudra. He was later known in Akkadian or Old Babylonian clay tablets as Atrahasis in the 18th century BCE. Clearly, the Akkadian Atrahasis was derived from the older Sumerian Ziusudra. This Ziusudra and Atrahasis were later called Utnapishtim, where he is better known in the Gilgamesh epic.