Dorothea and Michael,
these are all good points. One useful feature that I added on cvs head (will be the 5.0 release) is that you can sort the list of threads (questions) not only by the date when the question was asked but also by when the last answer to the question was made. This way you can float questions to the top with recent answers.
Filtering to only show unanswered questions sounds like a very good idea and should be easy to add as well.
