> or is it just a matter of waiting until someone has time
Chris Klimas (aka klembot) is the person who decides what changes are made the Twine 2.x application itself, so you will need to wait until he has time.
note: I added a comment to your PR about which special passage tag to use to indicate that a Passage contains a base64 representation of an image, and which of the current modern story formats include support for such passages.