I think this has been a problem ever since we had the launcher: Most players don't have a clue what the settings for shaders, particles etc. actually do: Which features are disabled under which conditions, and which are options that have a big impact on performance (frame rate). Much of this is not even clear to me after all the years.
For example, many players have no idea how to disable spell effects, which tend to completely freeze clients on weaker hardware during game events with many players using magic. (The answer here is setting shaders to lowest, which is not quite intuitive and implies terrible full bright looks on most meshes.)
So, a wiki article with some "official" guidance would be really welcome, and tooltips in the launcher are actually an even much better option. What are your thoughts? Maybe somebody has already written an unofficial guide and wants to share it?