I want to respond to this as I think you just have a fundamental misunderstanding on how wealth, relationships, and childbirth can be related.
A child is not made by the equation (One Female Parent + One Male Parent) + Marriage = Child.
This is not the actual requirement. It just requires sperm + ovum + body to carry the organism to birth. I interpret your comments here as attempting to take a purely logical/fact based approach, but you tie yourself to an unnecessary old fashioned notion of one man and one woman in a contractual union.
A woman and two men can absolutely be parents by inseminating the woman's eggs with their sperm and having someone else carry it, or artificial/manual insemination involving other women. I don't think you take your idea of efficiency here anywhere near the much more natural and sensible conclusion of "for-hire birthers", which already happens. A person, regardless of how they identify, should be allowed to do this; for simplicity sake though, I don't see why you don't mention this in your model -- a rich woman, paying for successors, and having multiple male partners who meets her scrutiny/desires raising the children and passing on genes/knowledge/personality traits.
You can suggest that your ideas imply this possibility, but frankly speaking I don't accept this suggestion; if you meant it, you would just say as such and/or use neutral terms for identifying the progenitors in your examples.
