As I've mentioned, I'm a maths dude, and I learned LaTeX to produce my thesis. Years later, I used it to typeset a non-mathematical book for publication. It's generally easy to spot a LaTeX-based publication, because folk don't stray much from the defaults, especially the fonts, but I managed it without too much effort. The main work is learning the ecosystem and, as I suggested, that does take time. However, the quality of output is very hard to beat, even with modern typesetting packages. Unless you have a genuine need for it, it's pretty difficult to justify the effort. But I could say the same about learning to paint, or play an instruments, and so on. I enjoy being able to produce beautiful text without much effort when necessary.
Markdown is great for general output. I use Ulysses on the iPad, and it can produce surprisingly good output with its extended markdown. (I use Scrivener on OSX, which also does a good job. I may buy Ulysses on OSX when it's on offer, at some point.)
Docbook is quite good, which leads into the whole Pandoc area.
But we're a way from maths at this point