The excessive use of shortcodes in the content to the point where the actual content is hardly recognizable in the midst of them.
The excessive use of custom post types in the production of what is intended to be a coherent piece of content (i.e. a single page or post). As a result, the content is scattered across many pieces that are all over the place, and hence needs to be written and edited in different contexts. Both writing and editing become a nightmare: The creative writing flow is constantly disrupted by the need to switch between editors, and editing becomes a desperate hunt for the pieces that need work.