It would be very useful, in View Templates, schedules, and other aspects, for Railings to have the Function property in Type Properties to be able to select Interior or Exterior. Other options coul dbe created, such as Stairs, Floors, Site (for fences), etc. Many other Revit elements have the Function property such as walls, floors, AND stairs. Often Railings are hosted to stairs. Without the Function property, a Filter has to be created. Filters are fine, but are extra added unnecessary work in some cases where Revit has short coming, such as Railings not having the Function property.
