My view in this regard is obviously biased due to the fact that I spent a great deal of time while crafting my research paper thinking about it, however I believe that perhaps the most important topic in Egyptian Archaeology is the issue of the Pyramids.
It is true that, in many ways, the study of the Pyramids has been overdone compared to many other aspects of Egyptian Archaeology (and indeed, archaeology overall), however this is precisely why it is so important. I would highly doubt that there is anyone in the world today that has not heard of the Great Pyramids of Giza. They have become such a source of wonder and awe, and have been since the time of Herodotus, how could they be anything but important?
The Pyramids are therefore significant because they inspire a sense of wonder in people, and therefore an interest in archaeology generally. I remember when I was in elementary school, I liked to write a lot, and one of the rather horrible stories that I wrote included the Great Pyramids and the Sphynx. While I would not consider myself to have been a totally normal child, my perception of Egypt, and the past generally, was very much informed by a knowledge of the Pyramids. In many ways, they were some of the things that got me interested in history and archaeology in the first place. Therefore, simply for trying to get people interested in history and archaeology, the Pyramids can serve as a very valuable topic.
The Pyramids are also significant as far as combating pseudoarchaeologists, who are intelligent enough to realize that the Pyramids inspire such a sense of awe in the average person. Because of the fact that everyone and their mother know about the Great Pyramids, they use them as a prime source for all of the whacky ideas that they develop, and since everyone has an interest in the Great Pyramids, they can use this to spread their ideas. Thus teaching about what archaeologists know about the Great Pyramids, and the other pyramids that have been created throughout Egyptian history, is a significant way to combat pseudoscientific ideas.
I will admit that, as far as the overall field of Egyptian archaeology in itself, the Pyramids may not be the most important topic, however when one considers archaeology as a whole, they are very significant. If we wish to continue to learn about the past, and inspire people to inquire about the past in the future, then we have to develop ways to get people interested in the first place, and the Great Pyramids are one way to do that.