The markup should be easy to describe and explain. This requires it to be [EasyToLearn], but also places some additional requirements.

The concepts used should not be new, but also they shoudn't be overly advanced (e.g. using CSS within [RawText] to style elements seems a little too complicated).

It should be possible to describe the [Creole] syntax in [Creole] itself (the {{{ } } } }}} issue makes it hard now).

All elements should be visible (even when printed), both in [RawText] and on [RenderedPage], so that they can be demonstrated to the audience.