A while ago I had about the same feeling and thought adding some categories would help to structure information.

Several categories have been added since.

Looking at the results today I feel it has not helped at all.

People do post whereever they want.

~70% of the overall number of threads/posts are in the PBP category
eventhough there would have been more appropriate categories for many of the threads.

As long as there is no moderation I feel we don't need any more categories.