Add a single text field called "category" or some such descriptive field name.
In each record of this table enter text into this field to identify the record as "Director", "editor", etc. To display all records in the "Director" category, you'd then either perform a find (on a layout based on this table) or set up a filtered portal that filters the portal records to only display records in the "director" category. While you could set this up with different layouts with a different filter on each portal, you can also add a field to your table and to the layout where you use a value list to select a category, then your portal expression compares portal records to the category selected in this field to control which records are displayed.
Note sure why you want to add a field named "agency" to the same table more than once...