I finally made the hard decision to give up and start from scratch with JoomD. I am SOOOO happy I did! This extension is exactly what I needed! It's very intuitive, and has enough functionality built in to really make your directory site complete. If you're familiar with php & css, it's also fairly intuitive to play around with the code in the back end to really customize your site, if you know what files to look in. Support isn't always immediate, which is understandable, considering you're not paying for it, but if you're patient you will get help.
Some of my favorite features are:
Easily attach an item to multiple categories or even multiple types/sections
Many diverse field types, including an address field which displays a google map of your listing
Search page allowing users to search by whichever fields you choose
Back end statistics display
And there are plenty of other useful apps available to buy for this extension, which I'll definitely be exploring in the future!