One way to manage this is to create server groups. All Named Users could then be pointed to specific servers, which would be dedicated for their use. Concurrent users, would be pointed to the other servers.
This configuration generally falls inline with concepts of why one would want mixed licenses in their environment. The bulk of users may be assigned to concurrent licenses, but the remainder are assigned Named User licenses because of their role or function. Upper Level management, for example, may be granted Named User licenses because you need to guarantee them (as much as posisble) access to their reports. If these users have to wait for other jobs or processes to complete before they can access their data, then they might be very unhappy (which rolls down hill to you, the administrator).
~Kurt