I think that clarified your particular relationship perfectly and it's beautiful that it's evolved to that stage for all of you. Awesome !
And doesn't it kind of point out something else important that we maybe don't talk much about ?
Let's call it "fullness"
I think there may come a point in everyone's life that we become "full". All our physical & emotional needs really seem to be met, our time seems to be all spoken for, and we tend put away the "looking glass". We're happy, content. I think this is just as true for conventional mono relationships as poly.
At this point, "more" could actually prove a complication & burden we just don't need. And at that point the rules seem to change.
I think it's a good place to "be" - maybe even what everyone longs for. And maybe you are there. For now
Wouldn't it be wonderful if everyone was ? And I guess that is the quest - and acknowledgment - of poly lifestyles. That it's maybe not realistic for many of us to get to that point with a single individual without infringing on THEIR individuality and needs.