A couple of suggestions/additions come to mind .. (Only if you find the time)
The ability for users to report a link which would send a PM to the admin .. with permissions so admin can decide what user groups can report.
In the Show drop down a "Random Link" option.
In the Description of a Category have a "Sub Categories:" list .. similar to how the forums show "Sub Forums:" on the forums front page. With an on/off switch in the admin area.