The fact the site includes trip reports was a major reason I joined. What would make the site even more useful is if the trip reports were organized and indexed by geographic region, total miles, elevation gain/loss (if available), etc. I realize that it would take a major redesign to do so, but it would be much more useful to me when I am planning a future trip to be able to peruse the "Pacific Northwest" trip report section...
The Washington Trails Association website generally does a good job with its trip reports. WTA members have submitted in excess of 28,000 trip reports to its website. These reports cover day hikes, weekend trips and longer, making it easy to find a good choice for a weekend. Also, more than once I've made other plans based on the fact that a trail was washed out or there was major blow down.
They have a hike search page which, if you pick advanced options, allows you to choose from a variety of hike criteria, limiting results by geographical region, elevation gain, high point, features (lakes, mountains, rivers) and distance. It includes a full description, many from guidebooks (with the agreement of the publishers, of course), that make finding a hike a snap.
I wouldn't necessarily advocate such an elaborate system, but one that did organize the trips in a more logical fashion would help.