Make a change to the REST interface so that any attribute field, or say the Primary Display Field, could have an external URL. For example this REST URL
http://46.51.194.124/ArcGIS/rest/services/WebServices/NationalMonuments/MapServer/0/34663 is by default based on the OBJECTID field of the Feature in the service. It would be really useful if the URL could be say
http://46.51.194.124/ArcGIS/rest/services/WebServices/NationalMonuments/MapServer/0/DG00603 which uses a selected field, in this case the esternally published ENTITY_ID field.
This change would mean that any feature with an externally known identifier could be easily accessed at the REST endpoint without the need to Query. Therefore permenant links could be made to this type of URL therby facilitating linked data and Open Data initiatives.