Archive Contact Lists
I would love the option to archive contact lists. Currently, we can only "clean up" by moving things into folders (we have about 20, and I don't use them because searching is faster).
If it were up to me, I would delete lists we are not using, but I understand the importance of being able to access the lists on old emails if needed. Therefore, I would like the archive option to hide the lists from views (in the Lists tab and when selecting lists for email sends) but leave them accessible and restorable from a second tab under the Lists section.
This would make it much easier for me to find what I need when my coworkers create "new and improved" lists. They can archive the old stuff, and I wouldn't have to sift through 10 lists with almost the same title, wondering which one is correct—or worse, ask.
On top of that, I'm thinking this archive thing could solve the secondary issue I have with deleting lists: workflows that run based on lists, and smart lists built on other lists.