As an initial suggestion, how about naming this 'permanent' content 'All About Crystallography', and arranging it in ~ 5-6 sections:
- The sciences of crystallography (explaining what crystallography is in the context of geology, chemistry, biology, material science, mathematical group theory etc)
- The techniques of crystallography (introductory explanations of diffraction and Bragg scattering, and illustrations of laboratory equipment and large-scale facilities)
- The beauty of crystallography (with examples of crystal forms, tiling patterns, the type of material in the Ars Crystallographica booklet, etc.)
- The people in crystallography (short biographical sketches of 20 or so particularly noteworthy scientists, chosen in part to illustrate thematic approaches such as 'Nobel prizewinners', 'women in crystallography')
- The history of crystallography (Marv's idea of a timeline along which can move a slider that zooms in on the details of scientific and social progress at any particular period sounds to me like an excellent idea to develop).
Where necessary, of course, the 'All About Crystallography' site can point to related content already on the main IUCr site, such as the information about all the Nobel Prize winners at http://www.iucr.org/people/nobel-prize