It seems to us that utilizing departments, and sub departments is the best way to keep installations scoped correctly as people and systems get replaced. Having the ability to build a department hierarchy would let us keep all policies with "base applications" that everyone in a department needs to scope to. As an example; With no hierarchy, as it is now, we have "Web Dev" team, plus a "Web Dev - Design" team. For applications that all web developers need, we have to remember to have both the department and the sub-group scoped to the policies. Then the subset "design" applications are scoped to just the "Web Dev - Design" department (group within the Web Dev department).
Using static groups has the same problem as scoping individuals. They can be lost if not closely monitored as replacement or new systems are entered into Casper. Smart groups are limited in what can be utilized for the automated sub groups.
Maybe this would be a worthwhile feature request? Or maybe we're just missing something already built-in.
Create all your departments.
create a smart group that contains the subdepartments.
ie smart group called Web Dev
the smart group contains Web Dev-Design, Web Dev-PhpMonkeys, Web Dev-DBAs
Then if you need to scope to all of your web dev teams, you can simply scope to the smart group Web Dev
Does this achieve what your after?