Hi there
Was just made aware of this thread. Very exciting conversation in many ways!
Just want to say something about Tobias’ and my explorations into the Nordic Thing-governance, which is also circle based, consent based and domain based. The introduction of democracy in the mid 1800s was heavily criticized for being a lesser governance method, despite it aspiring to be more inclusive (while excluding everyone but selfsustaining older men).
Thing-governance is similar in many ways to the Haudenosaunee’s Longhouse-governance. And I imagine that similar governance-traits can be found in other cultures. Would so much love to see an anthropological/historical research on this subject.
Another point is one that Aristotle puts forth in The Republic, where he criticizes the Athenian democracy for several things and argues for a kind of natural governance - a proto-governance - that resembles both Thing-governance and Longhouse-governance in multiple ways.
A central point is that the primary need for governance, historically, arises when families (or tribes) gather and/or settle. Before that, all matters are resolved within the family. You could say that the family has domain over every matter pertaining to the family alone (which can be brutal, sure), and that they resolve these things without much formalization, but that the commons between the families necessitate formalized governance.
Thereby you gather a circle of representatives from families in a circle, each with their own domain. And since every family is self-governed, they cannot be overruled but will have to consent to every decision.
Of course the direct influence of the Haudenosaunee’s governance on both Quaker governance and the American constitution, would be great to mention as a direct inspiration for sociocracy. And I find Longhouse-governance to be an extremely beautiful inspiration.
But I don’t think there are many unique traits to Longhouse-governance (please correct me if I am wrong), but instead a tight connection to the organic, natural, sensical and logical governance that perpetuates everything in nature, and can be found throughout the world. 
Btw, Tobias and I made this presentation on both subjects in 2020:
