All your points have some validity. However, it sounds like you were honest and sincere with the client, but friction still developed. Maybe it was due to a lack of (sufficient) communication. On the other hand, everyone has their own idea about how things should be done and will tend to be critical if your ideas differ from theirs. One thing I've discovered in my "old age" is that it's possible to seem accepting and agreeable about others' suggestions and still do things the way I think they should be done. There is a real art to that! (I'm still learning.)
chas