Have a way of supporting deployment-specific data
A demo site should prominently warn people that it is a demo site, ditto for a review site.
One way is to load something extra on deploy, but that'll need to be hand made per type of data. Another is to use the Sites-framework and add data to that, a SiteConfig model which can hold any site-specific data. Review-sites are a bit odd, they don't exist for long, so a way to tell the site that it is a review-site would be useful.
A related thing: how to make it easier to customize which auth-backends to use. B2ACCESS and Dataporten is basically hardcoded today.