Suggestion to Ancestry.com:
Add the directories in the database "U.S. City Directories, 1821-1989" to the card catalog by location.
There are over 1750 cities in the database that can't be found via the card catalog.
For example, if you search in the card catalog for Amsterdam, NY directories you will get one link to the 1887-1890 directory database. You will not get a link/links to more than thirty Amsterdam directories covering 1867 to 1959.
Again, this is the same situation for over 1750 cities.
Finding these by location is especially important since the character-recognition is poor in the US City Directories database. Users would have the opportunity to browse these directories by location instead -- if they could find them!