I try to design package structures in such a way that if I were to draw a dependency graph, it would be easy to follow and use a consistent pattern, with as few circular references as possible.
For me, this is much easier to maintain and visualize in a vertical naming system rather than horizontal. if component1.display has a reference to component2.dataaccess, that throws off more warning bells than if display.component1 has a reference to dataaccess. component2.
Of course, components shared by both go in their own package.
