The question came up, when this post How should I typeset the physical dimensions of quantities? got closed for being off-topic. We discussed it in chat, and it seem to be a bit tricky. That's why I would like to discuss this here.
On https://tex.stackexchange.com/help/on-topic there is no word about typesetting or best-practices but both topics are possible tags.
In chat, I got linked to http://graphicdesign.stackexchange.com. OK, but where should we draw the line. I don't think that I would get an answer to this special case on this site. I think the question is the same as concerns about "space between value and unit" or "space between acronyms" or all the "upright or not" stuff. On TeX.SX, there are a lot of people who know a lot of stuff about typesetting AND technical issues, standards and so on.
I think, then that topic of typography should be included on the help page. For me, that's a major part of what TeX is about.
And for "best-practices". Best practices in technological or scientific fields are often international rules or standards like ISO, DIN ... If I search for a canonical answer to an issue about units, dimensions, and so on, I would always search on TeX.SX first.
So, what do you think? If you don't agree, we should start migrating all the "cosmetics"-stuff to Graphics.SX. Would be fine for me, too.