I imagine it would be too cumbersome to include something like that as an option for individual posts, but why couldn't it be something I can switch on/off on my own profile as needed? Let's say I'm having a rough few weeks, and I'm a little on edge, and I know that maybe I need to more carefully consider what I say to others for a time - I can turn on the delay option, and then only the person I'm responding to and people who follow me will be able to see my post right away, and then it can appear for everyone else after a set time frame.
So your own waiting period, shall we say. You hit the egg timer and if you don't go back and do anything, it publishes you after twelve hours or six or whatever. I think that's a great idea. Maybe ditch the "contribute" button and replace it with "comment" and "commit" with a pull-down timer or something. Then if I click on my name it'll show me all my comments, including the ones that are drafts, in a draft color.
That's an interesting idea. What if the non-follower visibility delay was initially set to say, 6 hours, but could be toggled by the user between 0 and 12? Spammers would not know that they had a delay, and users could adjust theirs as they saw fit? TBH I would probably set mine to 3 hours.