Allow items in libraries to exist in multiple groups or allow items to be tagged and filtered by tag.
At the moment, items in a CC Library can be ungrouped, or added to a single group. Often though (certainly the way I use them), items may belong to multiple groups. If for example I have an icon that represents the status of something but also has a person in, it could possibly exist in both the "people" and "statuses" groups.
It would make cataloging items much easier especially in larger libraries.
Either that or tagging, so each item could be tagged potentially multiple times so that I could then filter by tag?