Alternatively, I think the "civil union" stuff from about a decade ago was a step in the right direction, but it was insufficient. If we referred to the legal status of joining to be a "civil union" in ALL cases and separated it from the religious status of "marriage," that might be sufficient. In this case, "marriage" would hold no legal significance and have no legal restrictions; it would be left up to the individual religious institutions to decide whether to grant the status. I don't know if it would solve all the problems (probably not), but I can't think of anything immediately wrong.