A problem with structured text might be that for newbies it’s hard to remember the syntax. This could be easily solved like on wikipedia.org, which means adding an icon toolbar.
There would even more complex functions possible as uploading and transforming an image, defining a reference and inserting it into the code (putting links into a document is still one of the most time consuming parts of editing a text).
Maybe for some features there should be an extension to the structured syntax but this might be easily done by using Pipelines.