I am not particularly happy with the html5 standard for document markups. It seems more suited to websites, and cannot figure out what is a higher-level and lower-level semantic markup.
I am not particularly happy with latex. it does not have a sane syntax.
I am not particularly happy with xhtml. if <span> and <div> are so common, could they not have used <s> and <d> as common abbreviations, instead?
I wonder---is it possible to define my own xml language that every modern browser can render (e.g., if the document refers to xslt transformation rules, or something like it)? I would not want to start from scratch, but with a template, e.g., to define a subset of html4. I would want to define latex-like macro = tags (e.g., \section <-> <section>). it would not have certain latex features, like newcommand or def or ... . does such a latex-markup xml language already exist, with support tools?
this could then be easily rendered into either a browser-native html, or easily into a latex file---and it would cure a lot of the shortcomings above.