many times over the years (mostly in drupal 7), i have had to implement a field that stores the date a node was published. every single time, the client was dumbfounded that there was no field for that built in. i would love to see a core field in the node table that stores the publish date, just like the created and changed fields.
i'm sure this would fall way down the list in terms of priorities, and i understand that. just an item from my wish list.
kudos to the backdrop team, i am very glad backdrop exists. i look forward to having time to contribute.