Just a few comments in what you state here.
In her funerary aspect, she was known as ‘lady of the west.’ Each evening she was considered to receive the setting sun (Red sun), which she then protected until the morning. This is the sun many times appearing amidst Earth’s thick band (as in wide) of debris as it set in the west.
The sun sets red anyway, as would a close passing comet. However, dust from a close comet would cause the sun to be red not just at sunset, due to loading in the upper atmosphere. A band of debris around a planet tends to be in a thin disk about its equator. I would say that it would be too thin to cause much scattering of light to make the sun red, and even then it would only occur when the sun was inline with this band.
Something else against the primary comet association would be Hathor’s longevity, she is attested to from the earliest of times, a perennial universal deity spanning some three millennia. Comets, on the other hand, although possibly remaining in the skies for several months, are too periodic.
If the comet was in the inner solar system (where its aphelion is in the asteroid belt), and if it is large enough, then its periodicity does not matter, as it could appear as a bright object all year round (or even for the vast majority of the year). Comet Encke for example has a period of 3.3 years, and could be as much as 20,000 years old. This to me suggests that once in the distant past it would have been far larger, and brighter, and comes very close to the earth.
Admittedily there Hathor may not be influenced by a comet, but I think that it is more likely than earth having a planetary ring in historical times (why would it just be the egyptians that recorded it, and not the sumerians and other contemporary civilisations, such as the chinese, who recorded detailed astronomoical observations??)
Anyway, I am just playing devils advocate. Although I find the premis that much of mythology was influenced by the appearance of a close proximaty comets, it is a highly subjective subject, with very little evidence to support it.
I would really recomend reading the books, if you have time. I do think it is worth considering as an alternative counterpoint to you ideas.
This post was created using 100% recycled electrons