I would like functionality that would facilitate rapid rollback of a published library. Such a feature would facilitate returning the previously published library to being in use in the case that a severe issue cropped up with the most recently published library. This could take the form of rebuilding a library in the publish history / column, and should probably cause the rolled back library to return to development status, or possibly adding the option to rollback the currently published library sending it back to development and allowing the previous library build to resume its place in production.
Currently performing a rollback requires determining all of the changes between what was most recently released and the previously released library, and then creating new revisions of all the changes that remove the previous change (note that this is made more difficult without the apparent ability to select an earlier revision).
Ultimately what I'd like to see is the ability to return the current library in production to development status and allow the previous library to resume its role in production with a minimal number of actions required; i.e. open a menu and select rollback.