Yes, I suspect that learning Sumerian could be very fruitful.
I have suspected the Kassite leaders as being players for some time, and perhaps the Gutians were their forerunners? The Kassite name sounds much like the Hindu warrior class of the Kshatriya, but maybe this is coincidence, but there is also a behavioral parallel of 'foreign' elite dominance, which if such peoples, including the Gutians connect back to peoples like the Tocharians. The Mittani and Medes have similar characteristics, and operate in the geographic areas of interest.
They gained control of Babylonia after the Hittite sack of the city in 1595 BC (i.e. 1531 BC per the short chronology), and established a dynasty based first in Babylon and later in Dur-Kurigalzu.[2][3] The Kassites were members of a small military aristocracy but were efficient rulers and not locally unpopular,[4] and their 500-year reign laid an essential groundwork for the development of subsequent Babylonian culture.[3] The chariot and the horse, which the Kassites worshipped, first came into use in Babylonia at this time.[4]
6. Myres, Sir John Lynton (1930). Who Were the Greeks?. University of California Press. p. 102. Among the names of Kassite kings are some which appear to contain Indo-European elements, as though they belonged to families which had once used Indo-European speech, but had lost it as their official language, through assimilation to the people of Kassite speech whose movements they were now directing. Some Kassite deities too seem to have Indo-European names.
It was the Hyksos who brought the chariot to Egypt, and I suspect that the ruling class and the Hyksos peoples were not of the same stock as well.
If I remember my Herodotus correctly, it was the Medes who instigated Cyrus to launch the Persian empire. And the Medes (or the Magi?) were described as an exclusive clan a shamen, ala what Nicolas De Vere detailed for his clan.
Thus one has all the requisite type of people present in the right time frames to fabricate the Abrahamic religions and employing the myths of the day.