Right now it's spiffy enough, but simply giving us the ability to filter by "purpose" would make finding parties and people much easier.
The easiest way I can think of, would be to simply have a number of checkboxes for each of the "purpose" types (Mission, Trade, Quest, Hunting etc). This would look very similar to the chat window we all know and love. If you don't want to see all the trade requests, simply uncheck it from the party search selection, if you are only looking for mission parties, deselect everything else. It seems a simple enough addition, and should make our lives that little bit easier in busy areas
