A Geographic Coordinate System (GCS) provides a great way to impose a geographically-accurate coordinate system on your DGN model. The GCS has been part of MicroStation since V8i, and continues in CONNECT. There's probably a GCS already available for your part of the world.
It's already possible to attach DGN XYZ coordinates to a text field. It would be useful also to be able to attach GCS coordinates to a MicroStation text field. That way, we could place a point and an associated text label, and the label would show the geographic location of the associated element. As with XY coordinates, the geo-coordinates would update automatically if the host element is moved. It would be better still to be able to display geo coordinates as longitude and latitude, or eastings and northings.