So, something like jade then? If your annoyances are semantics and the verbosity of other markups. Roll your own semantics with +mixins, and otherwise, just write HTML, without the fluff?

Human readable, concise, fluent, and HTML is a lingua franca of its own. Even in jade, I still make frequent use of the :md filter for simple text, but otherwise, structure is utterly up to you. Markdown alone doesn't quite cut it even for CMS style 'content-block-goes-here' editing.