Well from my experience working like this is hard for one the assistant only has time to help you i a few lessons,i worked like this for one year
and the admin officer was always calling my TC in class which pissed him off with other teachers problems,i would have the class teacher help me some times but not that often,some class teachers where good and stayed with me all the time others never came to class.As you saying about no-native speakers most schools don't like to employ them,had to many problems in the past from them.

So please don't try to give us bullshit on how good things are,some of us have been here for a long time and understand whats what.