It would seem a practical and desirable function of the Favorites view to filter out resources that are not part of the favorites. For example if I have 4 modules in my project and I select 2 for a favorites, then I am in my favorites view and search for a class ('Command-n') it should only include classes in my Favorites view. Similarly when I view VCS changes ('Command-9') I should only see changes that are represented by my current Favorites selection.
Does that make sense? It is a similar feature to Eclipse's working sets. The only alternative I see is to create separate IDEA Projects with the different modules included in each project but that seems like overkill.
Thanks for you consideration.