After going live, I realized a Taxonomy gotcha.
For example, user may click on Audio Clips category, which is made with Book. No breadcrumb. Custom breadcrumbs works per node type only. This creates the same headache as Acidfree does.
Even worse, because I created each Audio Clip pages with Book, and I need node type to be displayed whether it is video clip or article when visitor clicks on a Term View, say "Trio", Audio Clips are listed as Book pages.
Like Acidfree, since there is no way to duplicate the Book node type, I can't rename this one and only Book node type to Audio Clip because it will change other places where they are not Audio Clips.
Taxonomy seems to be the hart of the Web2.0, and it took me a lot of trial and error to learn about it, but I am still not sure how to handle this. All the readings at the Drupal site are focussed on Blogging, which I am not doing it.