I'm intrigued by the Valorian Society model because it reproduces some , but not all, of the traits typically ascribed to northern Indo-European societies. You highlighted a section that vaguely touches upon the problem of in- and out-group interaction, but it's devoid of any discussion concerning out-group behavior.
The model as it stands appears incomplete because it fails to account for the sovereign individual's desire for honor and prestige that historically led to the formation of war bands and expansion of power through elite dominance of weaker civilizations. These invasions ordinarily involved collective violation of the sovereignty of weaker, out-group individuals (e.g., the indigenous inhabitants of pre-Indo-European Greece mentioned in the Sovereign Individuals book). The Valorian Society glosses this fact with the implausible conclusion that conquered populations were slaves by nature who explicitly chose to live as slaves despite the overtures of the Indo-European conquerors. Do those who refuse to submit to the covenant, presumably out of fear of trial by battle and the prospect of living a sexless, childless existence, automatically become the property of the Sovereigns?
In sum, the model's excessive formal equality will inevitably come into conflict with its respect for individual sovereignty.