Please post your feature request to just-created http://docx4j.userecho.com/, though of course feel free to discuss here first.
As that page says:
Here you can suggest features you'd like to see added to docx4j, or vote for features already suggested.
The idea is to be able to prioritise development efforts.
Use your votes wisely...
If it is for pptx or xlsx components, please put or in the title. ...