for a 100 page site, it seems to be creating a rich keyword home page
It seems to me that such a flat navigtion blurs the relevance of all other pages on the site, and it tries to get the Home Page to rank for all the website's content. It also makes for a pretty rough user interface for humans.
My take has always been to categorize pages. The home page should be broad in scope with navigation that points to various "categories" of a site. The 2nd level pages would then link to various pages with similar content. You can take the navigation as deep as you think works, as long as the navigation makes sense. Then, try to link to the deeper pages from within the content on your higher level pages. Just do it in a way that makes sense to your visitors.