Here's the rub to the dialogue you propose.
First, since we don't allow members to post their directory details, we've cut out a vast number of folks who would post for no better reason than to promote their directory. No loss there. I've read such posts elsewhere. Bleh.
Second, WebmasterWorld has been and continues to be home to the most competitive of web developers. Therefore many are not eager to step up and say "This is what I do to beat/best the competition".
That leaves room for a handful of non-promotional directory folks who are unafraid to disclose details of what may be their competitive advantage. Rare, but you've come to the right place as they're around here too. :P & ;)
FWIW, my version of directory customization trends towards mimimalist architecture. In other words, when it comes to the directory part of any website I'm not a big feature man.
I know that a currently popular version of customization is to allow visitors to add votes/endorsements to the directory listings. I get the value of service provider endorsements or negative disclosures. Unfortunately, as "voting systems" are now implemented I have ZERO confidence in the validity of the votes. Are the voters family? Are the competitors? Have they been incentivized to vote?
Short of requiring a small credit card payment before voting, to validate identity, I find the "value added" of most voting systems - as implemented - to approach ZERO. Therefore I haven't jumped on the bandwagon but continue to grope for a reliable solution in this area.
I know there are other add-ons that can be used to customize a directory but, when I consider them, I have to ask: "What is this site trying to be? A directory or what?" Often it's the "or what" AND, to my eye/experience, all the customization-stuff doesn't really enhance my experience of the directory's utility.
So, dvduval, to your knowledge 1) what customizations have enhanced user experience and, 2) how do you know that to be true?
Are there any reliable "directory industry" surveys of enduser experience?
Now there's an idea. :P