The so-called expulsion of the Hyksos that preceded the 18th Dynasty is terribly misunderstood by Egyptologists (in my humble opinion - big grin). I have concluded that this battle pitted one faction of Hyksos royalty against another. As usual, the winners wrote the history and portrayed themselves as native saviors of Egypt against "those evil-doers who tried to destroy it". (So, your use of this event in the study of race is I think misguided, again in my humble opinion.)
Here's another (although also speculative) way of looking at racial attitudes in the 18th Dynasty.
In my model, David is a composite of Thutmose I and Thutmose III, pharaohs of the 18th Dynasty. The elder David is described as "ruddy" and irresistably "handsome". But why would the Biblical author include such details? Could this mean that he was either lighter or darker skinned than was typical in the royal family? There is reason to believe that the younger David, Thutmose III, was on the darker end of the royal skin spectrum, perhaps due to inheritance from his father and/or mother Queen Isis/Sarah.
According to the Book of Genesis, Abraham fetched a wife for Isaac (David the Younger) from among his kinsmen in Mesopotamia. This wife, Rebecca, was the sister of Laban ("white"). So, there is at least the suggestion here that the children of Isaac were to be "whitened" up a bit. The twin sons of Rebecca turned out to be quite different. Skin color is not mentioned, but Esau was hairy and Jacob was smooth. Their parents were divided as to which was the right choice for succession.
We happen to have the mummy of Jacob/Amenhotep II/Sheshonq. It is described by Harris and Weeks (X-Raying the Pharaohs, p 138). "Although taller than both his father and his son, Amenhotep II bore a marked resemblance to both of them, especially to Thutmose IV, particularly in respect to their crania and teeth. His wavy hair was brown with gray at the temple, and there was a small bald spot at the back of his head." (It is apparently not possible to assess his skin color, at least according to Harris and Weeks, because it is too badly stained with embalming bitumen.) The hair of Esau is said to have been red and profuse. Unfortunately, we don't have the mummy of mummy of Esau/Menkheperre A/Saussatar for comparison. However, later pharaohs, such as Ramses II, are known to have had red hair.
Note that both Jacob and Esau had Mitanni (Libyan) names. The name Sheshonq connotes whiteness, although we can't be sure if this reflected his skin or just his assumed Mitanni/Hurrian identity.
Jacob, like his father Isaac, chose intermarriage with the family of Laban. The hair of his son Joseph/Yuya was light and possibly even blonde as evidenced by his amazingly preserved mummy. However, intermarriage with "Labanites" ended with Joseph/Yuya. The wife of Yuya, the equally well preserved Asenath/Tuya, has been described as more "classically Egyptian". She was not from the immediate family of Joseph, but we still have reason to believe that her pedigree was immaculate. There is also indication that Tuya's daughter was dark or darker skinned, and was the "dark but lovely" bride of Solomon celebrated in the Song of Solomon.
From mythology, archetypal Joseph (Enki/Ea/Ptah) was renowned for his practice of incest. The house of Joseph in the 18th Dynasty also rigorously pursued this course, and this is perhaps why Yuya was provided with an eligible wife who was as different from him as possible in terms of observable traits. The House of Joseph became so inbred that the boy-king Tut had only one set of grandparents, those being Yuya and Tuya.
So, what can we learn from this? First of all, racial qualities did seem to be important to the Biblical family of Abraham. However, they seemed to be important in the sense of maintaining a balance or diversity rather than an extreme. This perhaps fit in with the royal family's desire to be "all things to all people". It might also have been an attempt to identify with the myth of Atum ("totality"), a name which perhaps implied among other things that he/she was the source of all races.
© Charles N. Pope, US Library of Congress. All rights reserved.