For many identifiable types of articles, articles of a general type will be managed by one or a few particular subject areas. So, for example, we would probably want to set some basic guidelines for articles about philosophical classics, wars, battles, languages and dialects, countries, cities, professional/academic jargon, etc., etc. The editors of the relevant subject areas should--if necessary with the assistance of the editor-in-chief--identify such article types in their own areas and discuss, with their reviewers, any necessary or helpful guidelines for writing articles of those types. The guidelines should then be placed in the area-specific guideline pages for each category. (See "Setting category-specific guidelines for writing articles.")
Biographies are only one type of article about which we might wish, for the sake of uniformity, to make a few general rules. The bulk of biographical articles should consist of discussion of the person's achievements or "claims to fame" as opposed to relatively inconsequential personal data. E.g., regarding the entry about Descartes, there should be a much higher priority placed on discussions of his dualism, rationalism, and methodological skepticism, and the impact that these views had, than on relating the tragic fashion in which he died. Of course, longer articles may be exhaustive in all respects.
Articles on the most general topics, or "top-level" articles (e.g., "music"; "philosophy"; "computers"), will have special characteristics that can be specified in advance.
First, they should indicate "the lay of the land," the conceptual landscape that most experts explore in thinking about the subject. Thus in the introductory article about philosophy, after attempting a brief definition of the term, one would explain, for example, the distinction between contemporary philosophy and the history of philosophy as subjects of study, some of the main areas of philosophy (such as metaphysics and ethics) and problems or questions associated with them, and perhaps the fact that philosophy is these days pursued mainly in philosophy departments at universities, although in some broad sense people use and discuss philosophical concepts in many other fields and areas of human endeavor. One might also want to have probably an entire paragraph devoted to the question, "Why care about philosophy at all?" (The above is only an example and is not meant to constrain what the philosophy editor and review group might decide after more considered discussion.)
Similarly, with the topic of music, the top-level article might discuss, e.g., musical instruments, different kinds of music around the world and written vs. aural music, music theory, why play an instrument and how (in general) to start, why go to concerts, etc. What the topics will be will have to be a matter of choice for the brief article, which of course is as it should be. The longer general article about music might go into considerably more detail on the same topics and more, albeit at a still quite-general, schematic level.
Second, top-level articles should be content-rich, or contain a lot of information, even if it is information that would be obvious to many educated adults. That's quite all right; very well-educated people are probably not going to be so interested in the top-level articles on a subject. Also, and correspondingly, while we would wish to keep the articles as readable, well-written, and entertaining as possible, we would also like them to be full of information and to avoid rambling.
Third, in general, those responsible for top-level articles should look in other online encyclopedias or others you have on hand, to see what their articles cover. We do, of course, want to do at least as well. In many cases, this will not be difficult for us.
The editor-in-chief would be a suitable candidate for lead reviewer of all top-level articles. But in any case, the candidate should be particularly well-informed about Nupedia policy and expectations.