An important design feature for the next generation bibliographic framework
will be "catalog code neutrality". Discussons about "main entry, yes or
no" should probably be left to the cataloging folks; the new framework
should theoretically support any approach.
Attempting to restrict the new framework to a reduced element set will
probably be a non-starter a) since Dublin Core already exists, and b) since
each and every data element in MARC has been championed over time