Yeah, you're right about categorization needing to be generalized, that's certainly on our wanna-do list. The symptoms you see in existing code (packages rolling their own) are often an indicator that the aD folks were working under time pressure to complete a given package rather than sit back and wait for a better solution.
I don't think the item-revision structure of the content repository is so burdensome as to cause a text content-oriented package to avoid using it. Strictly speaking, for instance, the bboard package doesn't need revisioning (at least as currently implemented).
It does add a little overhead to the API and of course two items that need to be joined before content can be presented. But in return we get a simpler structure and a greater degree of commonality (well, the latter's more theory than a current truth given the fact that various packages abuse the CR to some extent or another - more stuff to clean up in the future).
