In general, tours are not very valuable. Students on tours are there with no context or immediate need. It is important to provide opportunity for tours. Tours do benefit some students. The guides they use are enthusiastic and well trained.
Tours do address some basic physical orientation questions.
A very basic directory would help. Simplest possible directory required. The Library and information environment has become more complex. Users are confused. Library web sites address very diverse audience which leads to formal tone and approach.