The most important part of a website is content, followed
very closely by ease of navigation, graphics/layout, and the ability for people to quickly find what they are looking for. Maybe it is just me, but the way something looks or is presented is just as important as the actual content itself. Neither content nor graphics should be sacrificed to the other, as both are very important.
But having nice content with fancy graphics is cool, but if you cannot quickly find what you are looking for, people will lose interst. If it takes more than three clicks for a user to get to
any page from the homepage, then you need to simplify things. Havign a search bar also helps users a lot. If they want information about something very specific, they are not going to browse your website looking for the page - they will want to simply search for it.
Also, having your website easily cached by
Google,
archive.org or other search engines is a major bonus. Having your website easily cached by Google or in the Internet Archive is a major help if your server is down or you get the dreaded Error 404 while looking for a page.
EDIT: I almost forgot up to date content! I cannot stress enough how much users to a website are discouraged if the homepage of a website is talking about how your team did at a regional three years ago. Having current information shows the public (at least subscionsciously) that your website is making an effort to provide the most current and useful information, which is usually what they are looking for.