Hi. There is a "poly families" thread in the Queer Parenting forum that is what you are looking for. I agree with you in theory on your idea, we tried it and it never worked out but then maybe we never found the right woman, and are now at a place in our lives where we're not looking for that. But I wish you lots of luck, I love the idea of extended family and lots of love.
Novel writing student Mama to ds (8y) and new DD 1-13-10.