Here's a suggestion for a future version of LISTSERV, perhaps the one
following 1.8b:
 
We have our local service area defined to be our own organization and
have many lists that use Service=Local.  We also have a lesser, but
still significant, number of lists that are intended to serve our
parent organization and all its components.  Right now, if those lists
are not to be visible to the whole Internet, each one must specify the
proper service area individually.  This is awkward when the definition
of that service area changes.  What I would like to be able to do is
define additional service areas that could be referenced by lists.  One
way of doing that would be to allow Service=(xyz-l), meaning "the same
service area as list xyz-l."