The abbility to have multiple groups/pools of license on the same license server would be very beneficial. Each group could be assigned licenses from any level (Basic, Standard, Advances) and extensions. Users can then be assigned to the license groups via Active Directory OU's/groups, or direct naming each user account. Any license should be able to be in one to many license groups, as with users.
We have a main pool of licenses, but there are several departments that want to ensure their users can access a license through the day. Single Use is too restrictive, and the Concurrent Use model would be perfect for the departments needs. It would be a nightmare to get the IT department to give us another license server, nor would it make much sense to have two different license managers.