Question to all, what has been your experience with non-technical SEO. What things are worth pursuing with limited resources, how to measure it and what are goo

Question to all, what has been your experience with non-technical SEO. What things are worth pursuing with limited resources, how to measure it and what are good resources to learn? I'm asking, because every time I read up on these topics, or interact with an "expert", I get the feeling, that it is one of the more snake-oiley fields around.