After a couple weeks of revisions, Later has passed Slack's review process and is now live in the Slack App Directory:
https://slack.com/apps/ANPGHD2F8-later
And so Later is officially open for business. But my hunch is the Slack App Directory won't drive much of an audience to Later unless I get included in their "popular" or "new and noteworthy" lists. So it's time to get busy laying the marketing plan...