Show newest nodes for each taxonomy term in Views
I was trying to achieve a similar thing. I've managed to create a view that gets one article for each taxonomy term using 'Taxonomy term: Representative node' under 'Advanced > Relationship'.

There is also 'Content: Taxonomy terms on node' there which might be more what you're looking for. 

Once you've got the relationship you can pull out fields and base filter criteria on that relationship. My view only returns 1 content type for instance.

Make sure your view is on Taxonomy not Content.