Customers (Banks and retailers) are finding it difficult to trust the cloud with their business data and the fact that data can be store in any location in the cloud as a result not adopting HDInsight at expected rate.

It would be great if the HDInsight 'namenode'/'head' is able to create nodes on-premises data centers such that 'vital' dat stay within customer premises and other 'none sensitive' data recide in the cloud storage.
Benefits: customer can run jobs across location and only need to move limited data to cloud (cost), they are rest assured.

the headache of managing the DR for namenodes is also removed as that is the cloud and a copy can be replicated to on premise server.