''In the Book of the Dead papyri of Ani and Hunef-er, both painted in naturalistic hues, the great majority of humans and deities are depicted with light or caucasoid skin coloration''

If you are talking about the picture of ladies puring sand oiver their head in the scene or mouring this is purely symbolic,and not actually their skin color.

I notice you avoid other tomb scenes of people like nakht,and the baquet scene which show the people as dark brown,not light caucasoid skin as you call it.

I donot denmy that northern egyptains especially aroudn the delta were litghter complected as they are today,but majority of upper egyptains would be described as black if you were to see them.

THe nofret statue is form the fourth dyansty which shows intermixture sionce the first three dyansties come form the south upper egypt.