Good directories do much better than that. Nor does the value come from rating mechanisms and etc. Good directories add value by contextualizing, sorting and analyzing infomation better than a search engine does. They come from not merely *describing* the site, but describing it better than it describes itself. One good way is to really *evaluate* it, based upon domain knowledge your reader may not have. I don't know a whit about German history, but I know it's a rat's nest of opinions. A cool-headed and knowledgeable web directory is the best bet.
Directories are particularly valuable where search engines fail. I see two main categories, (1) high-commercial topics that get infested with SEO junk, and (2) troublesome topics where link-building dynamics fails to predict what *your* users want.
The latter is my main interest (alas, not a very commercial one). For example, take an adult interested in a "kid" topic, like dinosaurs, hieroglyphs or explorers. Google is nearly useless. High-PR educational are one problem. Their content might be good, but it's not for adults. A larger source of distortion is the school resource page and the school report. School resource pages are, of course, geared to kids' sites, a kids almost invariably link to one of the top sites, no matter how wrong or old. I'm fine with links being votes, but kids shouldn't be able to vote!
More generally, spartan directories are like annotated bibliographies. More full directories are like book reviews. The existence of library catalogs hasn't put either of these genres out of business. Search has certainly gained in use as search engines gained in usefulness, but they will never eliminate other ways of finding information on the web. After, what are the majority of blogs but focused, unsorted, highly-annotated site reviews--directories by inches.
A good directory therefore provides human-evaluated, structured, knowledgeable and well-written alternative to SERP soup.