There is a way to configure initial site content that is populated when a new site is created. It may not meet your needs since it only works at the time of site creation. It was designed for use on my demo site which is re-created periodically with the same content each time. The pages and content are defined in xml files so there is still some work to create those files and test them to make sure they are doing what is intended. Once the files are defined and working they will be used to populate every new site created in a multi site installation after that. Or the files could be deployed also with a clean install of mojoPortal so that the first site created during installation has the content created.
See Configuring Initial Content
I have no other solutions to recommend, so if that doesn't meet your needs you'll need to come up with your own solution.
Hope that helps,
Joe