In a nutshell
I would like to have a way of saving draft posts and managing the time at which they are posted, creating a queue of posts from me that are spread out through the day, respecting the post reward rate limit
The problems
My creativity (hint: it's not just mine!) doesn't work on the clock. I have days when I can't write at all, there are others when I wake up and make a list of posts and can barely knock them off slowly enough for them to make any sense. Currently, being prolific in a short space of time is penalised by the Post Reward Rate Limit which (in order to deter spam) reduces the rewards once you post more than 4 times in a day - with this in place a "good Steemer" posts once very six hours, and no more. My Steemit time needs to fit in around the rest of my life rather than me having to synchronise myself with the Steem-clock.
Workaround
I could keep a text file of my drafts and to pick one out when I'm online and have time, I copy and paste by hand - have to separate out the title from the body and from the tags I've chosen. 
Prior art/ other interest
I did a quick search for prior art - if you look for "queue" in the Steemit Search, you get a lot of articles about the miner or witness queues (I don't know exactly what these are, but I can imagine) plus some using the word queue to describe a feed ("a queue of new articles about..."). Of course there were also some people talking about actual queues, lines of people waiting for bread, or ribbons, or their paycheck.
User's experience of a solution
My experience should be just the same as writing a normal post. There would be a button marked "Add to Queue" or similiar alongside the existing "Post" button.
Tumblr has a similar function - it's implemented as a dropdown on the "Post" button
