As for issues, I've suggested to GitHub that they make them available via git, and they said simply "I have passed your suggestion on to the team to consider adding the ability to clone Issues". I don't think they realize how nerve-wracking it is to put any data at all in GitHub issues. Even their recommended backup software is out of date and doesn't back up Issues completely.
GitHub, even with relatively recent issues and downtime, has better infrastructure and skilled personnel than most companies hosting their own instances of these services on some reclaimed box.
You need those database backups.
I haven't checked GitHub specifically, but most of those terms include, "and we can ditch you any time for any reason, maybe with 30 days notice if you're paying"
If you want to take advantage of their infrastructure, that's fair, I understand, but at the very least, run some tooling to backup issues, pull requests, wiki pages, etc on a regular basis.