I remember those days well, in 1966 I began my first real job, working at McDonnell Astronautics on the Skylab design. In all my working years since, I have never worked with a group of individuals who were more professional and dedicated than that group of engineers, many of whom had worked on the Gemini project.
I agree with everything you’ve said, but let me add one more item to your list, ‘Managing risk’. I believe the items on your list were the product of identifying the largest risks involved and minimizing the probability of those events going wrong through better design and training.