Allow multiple template documents to be associated with a content type
Optionally allow content types to point to a templates library, and include all documents associated with the content type in that library in a sub-menu when you click New.
Consider for example a content type called Report. The same content type would probably be used for many different types of reports.
It would also be nice to allow templates from a number of different libraries to be included. That way you could provide for corporate templates, departmental templates, and team or site templates.