I have been using MDS since sql 2008. When I have the business user asking for changes to the MDS model, one of the request that I continually keep getting asked is conditional domain attribute filtering. An example can be seen http://blog.contextures.com/archives/2013/09/26/conditional-drop-down-lists-in-excel/. This would help the business user in not corrupting the member with invalid data. Another example that would be useful is in a workflow process where you could only select next available state/s.