When trying to fill a bug, it's unclear in which category to fill it since there are zillions of categories on the first page of bugs.kde.org. Some structuring would help (e.g. KDE Apps/Frameworks/Plasma/Services/Websites). Example: if I want to report strange behaviour of printing dialog that I noticed, let's say in Okular (but it is not app specific to okular), it's not immediately clear where is should go.
In fact, that wouldn't help you since Okular's printing dialog is provided by Qt. :) The best you can do is report it anyway and a friendly helpful bug triager will route it appropriately. As for your request, I completely agree. We're currently waiting for a new upstream release of Bugzilla, and then we have active plans to do this. Marking as RESOLVED LATER since it's on the roadmap but there's nothing we can do right now.