I like the ability to show and hide fields sets based on conditions, but I would also like to see the ability to show or hide individual fields within those sets. My primary interest is in hiding individual fields that are blank. This would make it display nicer for users, but could also, if you were able to set the condition to only show blank fields, allow for a field set that shows only those fields that are missing data and still require user input. That would make it super easy to gather missing information. You could also add potentially use this to add a field set at the bottom of a page that is editable which says "requires further input".