I enjoyed reading Quintilian, since, as Morgan and Karen pointed out, he seems to be a rhetor whose teachings on teaching are closest to our current teachings. And although we may quibble about the importance of the rhetor being morally fit, it is not far from the expectations we have of teachers now. In South Carolina, for example, my sister was not allowed to be seen in town consuming alcohol...to ensure she was a good moral guide to her students.
Some random thoughts: