I have recently checked raar’s hosts and he seems to have local bots working. That is, upon someone joining his hosts, a bot is automatically added and a game can start immidiately. We could use this to both have something prepared for newbies AND to have mission hosts (e.g. westerplatte invasion or normandy invasion) where some AI would command a lot of pre-placed units and the mission would be to successfully invade in a given time or resource frame.
This is now working with a caveat: spring headless does not exit when the last human does so.