If you already know about vim and how to use it, is this course really for you?

No, it's not intended for me. I'm actually evaluating it for other people (I work with people that are totally lost in Unix shells) and playing with its terminal to see exactly what I've been given.

We have actually been thinking about expanding on this content with more advanced stuff, including symlinks and permissions.

I'd encourage you to make it more incrementally advanced, i.e. progressively more difficult toward the latter third of the course.

After you get past that, maybe some basic scripting would be in order.

The course needs more content, through and through. You've got a solid beginning, though.