Couldn't you add an intermediate level between tribe and individual of family? There's been plenty written on the benefits of an intact family for the overall well-being of it's members. I find that "what I really need" greatly expanded when I try to plan for my progeny's education and launch into adult life, as well as hedging against emergencies and family support for life after work (or life after me). I'd be at a much different point on the grasshopper-ant spectrum if it were just me.