What would be and interesting addition would be votes / fav lists per category, so that there would be kind of a competition for up-votes / favs. Each category would have a separate page where it listed the top votes for each category w/ the admin option to list 5, 10, 15, 20, etc. number of items on the list per category. These category list would be in addition to the normal links pages.
If there was an additional option to "pay to vote" where a member could buy extra votes from the store to get his link ranked higher. Have widgets which would display top 10 lists for each category or an overall top 10 list.
Would end up as a competition for the link owners to get their links ranked higher on the lists. Which would give the link owners, more views, more visits, etc. to their site.
Just an idea.