Is this the sort of thing you would expect to see?

That looks fine to me :-)

Do I need to make a 'release' or 'package'?

On github? No, I would not bother. You have PAUSE and CPAN for that. So long as your repo includes the user-level instructions for obtaining and installing (which it does right there in the README.md) there's no need AFAICS to duplicate the release effort.

Do they set the point at which development becomes a version?

Github? No, I cannot see how or why they would.