Dear Vikrama,
Point 3 cannot be measured and it is based on perception of students. Also I want to clarify quality of teaching is not only depth of knowledge , but a complete package of contents, context , relevance, presentation etc. In Online teaching , even clarity of voice can be a quality differentiator.
Point 4 is an interesting perspective. Here a online teacher is like a company which allows working from home. It gives a confidence to the students that you are reachable in emergency. That goes a long way to create a brand. But I am not sure how to quantify it.
Regards
Puspita