I would like the ability to set a default knowledge agent for specific users and/or groups.  Guru has primarily been used by our customer support team for accessing cards related to user issues.  We are expanding to now use Guru as a company-wide knowledge base which will include cards on many internal topics from IT, HR, Finance, etc… All users will have access to this content.  For our customer support team, we would like their default search to only be in the collections related to user issues.  If they want to search for an internal IT or HR card they can switch to the Guru (or some other custom) knowledge agent to search all collections.  This would be most easily achieved by setting the Customer Support group to default to the Customer Support knowledge agent which is limited to the Customer Support collection.