I have appreciated the effort that my teachers on italki have put into my lessons. They provided ebooks and assigned homework assignments to be completed before the next lesson. They were flexible, both with lesson times and with the content of the lessons, and were very patient. They were also quick to communicate via messages on italki in between lessons. I suppose I wouldn't stay with a teacher that was uncommunicative or inflexible about what I wanted, or that didn't seem to put in any effort outside of class.

This is a great question. However, I wonder if you might not get more information by asking it in the discussion section.