I think solo poly people (who do not wish to be partnered) are very similar to what you describe as open, regarding what we want (except for, maybe, being okay with DADT). Being solo and having no wish to cohabit with anyone nor have a partner, I have wished many times that there was a place just for others like me, or a resource online for solos, and I might eventually create one myself (if I ever feel that motivated).
But yeah, the couple-centric focus on married poly people and threads about kids and families does get tiresome after a while (in any of the poly forums I visit, not just this one) when you're solo and childfree. I just avoid them for a while, answer the ones that I relate to better, and then revisit those dyad-focused ones when I have gotten over my feeling of over-saturation. I do learn a lot from every walk of life, so even those married people and parents have something to offer me.
I do have to say, I was very, very turned on when I was in bed with a guy I was seeing last year, Burnsy, and saw the wedding ring on his finger as he played with my breasts. It felt so forbidden!