Today I finally finished recreating the Photo Directory. (I kept at it for days, chained to my desk, without wasting time on less important activities such as eating, sleeping, or breathing.)
The Directory now points to photos in member profiles as well as the photos in the "Pics!" thread. However, only 6 of 154 members in the Directory have submitted profile photos so far.
I assume that there is no way to trigger a notification when a photo is attached to a profile, so I'll have to check for them periodically or depend on people to let me know when they add one.