Hi Mark,
This is a very interesting scenario. I didn’t specifically think of this scenario when I designed DocumentAssembler.
One idea that I’ve had cooking for some time is to enable importing XHtml content. In this approach, you would convert your text to equivalent XHtml (or an approximation thereof), and DocumentAssembler would use the HtmlToWmlConverter module to convert to DOCX. Then, separately, I would enable the use of DocumentBuilder to import that new DOCX into the generated document.
This isn’t a huge amount of work – a few days at most. However, this is not currently in my schedule. (I am doing some super-cool Open XML work currently, and will be blogging about it soon.)
One approach you might take – when you see this content, insert some special tags in the document, and then post-process the document, making it as you like.
I’ve put this on my list of projects.
-Eric