Library Feature (sort of like Acrobat's "Collections")

I love Scrivener and have used it to write books and articles as well as organize notes and concepts for my business.

I am often wanting to go back to or find a project file that I want to update or reference that is older than the Recent File list. I’d love to have a Library feature where I could hierarchically store and organize lists of my project files (ones I choose to be in the Library).

This could appear as any of the following:
• In menu form (as in Acrobat’s “Collections” under File->Organizer) or
• A separate window view kind of like the corkboard
• Another item on the navigation bar on the left
• Another icon next to Inspector that would make a different vertical workspace appear where the Inspector items show up.

Thanks for a great product!