I can't agree more. Maybe the control of content by others can be problematic, since when that is allowed, then censorship may happen. At Steemit we have the flag option, but the content is still visible. The content itself is not encrypted stored in the blockchain, ie everything and everybody can read it. Another social networks out there with blockchain encrypts the content first and provides the feature of permissions; That would be great for Steem blockchain to implement. When we get community features, this would be a great addition to that feature.