Wouldn't it be nice if we could designate certain Collections as Parallel Resource Associations (PRAs)? I would actually call them PRCs - Parallel Resource Collections. I would suggest that these PRCs should show up in our Library like other resouces - they would just be bolded or highlighted to show they are PRCs. The order of the resources in the PRC would be set (ranked in a prioritzed order) by the user. When you opened a PRC, only the first resource (the highest rank) would actually open. The other resources in that PRC would be shown in the + tab as parallel resources, so you could then "arrow" through that list as necessary. It would be important to have ONLY those resources in that PRC listed as parallel resources, and not any others that Logos may normally list for that resource type.
In this way, a particular resource could be listed in multiple PRCs without conflict, since the user would be opening a given PRC, rather than just a particular resource.
PRCs like this would give version 4 way more power and flexibility than we ever had with the PRAs of version 3.