The preferred model of family

Here's some questions in light of the Nia Glassie and Kahui abuse cases.

Should marriage and commitment be promoted among Maori instead of merely condoning living arrangements of kids who live within extended whanau with one of their parents who shacks up with whoever they please?

Anybody want to comment that a preference for a model for the family should be mum and dad and their children? Should this be encouraged and supported in public policy as it is likely to be the most stable type of family - just as Maori children who live with two adults that are not both their mum and their dad are more likely to be abused than any other children?