I just wrote an entire book in asciidoc and honestly I don't like a lot of the decisions and the syntax, the tooling is also quite messy and hard to use/configure.
Having said that, I'm not sure if there's really any alternative. If you need the extensibility and diff-ability of asciidoc, then you're probably going to have to use it. If you don't need it, stick with markdown.
EDIT: so that people get an idea, I use asciidoc because it provides callouts, sidebars, captions, figures, cross references, LaTeX (via hard-to-use plugins), themes, fonts, etc. when converting to pdf or epub, etc.
Having said that, I'm not sure if there's really any alternative. If you need the extensibility and diff-ability of asciidoc, then you're probably going to have to use it. If you don't need it, stick with markdown.
EDIT: so that people get an idea, I use asciidoc because it provides callouts, sidebars, captions, figures, cross references, LaTeX (via hard-to-use plugins), themes, fonts, etc. when converting to pdf or epub, etc.