I found this in an old thread and thought it deserved its own, for ease of discovery and further discussion.

What I'd like to know is, in group worship, is only one person in the "Priest" position (like in the Christian Mass) or is everyone a "priest" (as in Wicca). Your reference to the Bast procession seems to imply the latter, but I'm not familiar with it.
In traditional temple religion, you would have one person who actually went into the holy of holies- to actually present the token bread and water offering, and clothe, wash, and touch the god- but several support priests to perform various tasks such as holding the scroll from which the ritual words were read, handing appropriate ritual tools to the head priest, possibly pouring libations, carrying in the offerings of food and flowers which were laid outside the netjer's door, and quite likely answering in chorus during the "call and response" style hymns which seem to have been popular back then.
During festivals, these temple priests would perform their rituals privately- there was no congregation to witness. The people would be outside the temple, celebrating in their own way- usually with feasts, drinking, dancing, and generally having a great big party. I tend to think that most "public" Kemetic rituals which are really trying to be traditional would do better to take this model for inspiration, and in the later years of the Bast ritual this is what they did. There was a group of people who acted in the capacity of priests, performing a simple ritual and offering in honor of Bast- then the folks outside were invited in for dancing and celebration. Occasionally, in ancient times, the gods would be brought out among the people, where They would be available for oracles, but these were special occasions. The Bast ritual tried to incorporate some of this as well, with a procession just before their celebration- though they never got so far as giving an oracular consultation. Perhaps that's just because the people who were around at the time were generally not Kemetic, and didn't know they had the option? I wonder what would have happened if they had?
Regrettably, we know very little about the daily practices of the common people in ancient, and so most of us hypothesize and infer from what may have trickled down from temple practices. This is why so much of what you see in modern Kemetic ritual involves people acting as priests, even though not everyone is or needs to be a priest in this religion.
In my temple, we gather at regular intervals for group worship- and in those gatherings we each take responsibility for bringing some portion of the offering, as well as taking turns speaking portions of the liturgies during the actual ritual. Some of the liturgies we use have been published, so if you really wanted you could see the sort of role assignation we use. We don't have any member who is considered to be the "head" priest, and we have no king, so we try to keep it fairly democratic. After the ritual, we all sit down to a meal together with the reverted offerings.
In my experience, however, Kemetic ritual doesn't really require a large number of people to worship in close physical proximity. The Kemetic lifestyle requires us to live in balance and ma'at- and for that I believe that other people are needed, because it's really hard to have a balanced relationship with only yourself all by your lonesome. But for this, the people around you need not be Kemetic- they only need to be a part of the world in which you live. The only advantage to having a group, in my opinion, is that with a group we're able to supply a larger offering table, and possibly supply a greater range of equipment. Otherwise, there really isn't a need for a large cast in the ritual itself, and I find that most rituals flow quite well with one person doing all the speaking parts.