The problem is that this is a moving target (and event more in motion due to Microsoft's need to port this to some mobile platform, so no matter how much is invested in this issue, they will never get close to acceptable.
I've written a bunch of Perl code (that I should open source.. maybe some day. anyone here'd find that useful?) for creating and editing docx files. It's not that hard -- it's all XML!
EDIT: I was using a LibreOffice daemon before, but I did this code just because Libre had so many bugs / missing features when converting a document to docx.
It's too bad the Oracle didn't take OO under their wings. With their resources they could have turned it into a true competitor to MSO. As it stands now, volunteers enjoy adding new features not bug fixing or scouring the 200 page OpenXML spec. sheet.