I am not really sure what you mean.
The very few settings left without visual examples but are only spoken of, are such that do not strictly change the look of the render. These are fine-tuning tools, rather meant to affect sampling calculations which are of secondary importance and higly depend on the current project. They rarely manifest visually or as render time time boosters. Giving you the math and alogrithms behind them is beyond the scope of this training. There is no other way to inform you of their existence but "talking" about them. Using the defaults of such parameters is often recommended.
Additionally, there is a pretty good example of how to optmize (improve speed while reducing fireflies and other visual artefacts) for Path Tracing / PMC.
Due to the nature of Direct Lighting and InfoChannels such actions are rarely needed. You got everyting you need to know (and everything that matters) for rendering images quickly and noise free, without sacrificing quality.
If you expect the VRay way of doing things - with a 100 parameters and black magic skills, well this is not the case. Image quality in Octane is controled via a very few parameters, which were clearly explained and demonstrated in the respective chapters
So yes, I will say it again - do experiment with the settings that matter. Values will be different based on your lighting and material set ups. I cannot give you some hard-coded numbers that magically work for every scenario. You are shown how and when to use the proper tools. It is up to your fair judgement to put them to good use.
Please, let me know which "crucial aspects" of the render settings were ignored. I will gladly take the time to clarify their uasge if needed.
Once you find a place or resourse that explains render settings better - do share! I will be thrilled to check it out.
Thanks for your time.
Dobs