Thanks - in fact bgruber's video link above [1] about R7RS-small also includes a section about R7RS-large too. I hadn't seen the video when I asked my question. Basically another working group will work out the details at a later date and it will be much larger - about 80 packages and probably bigger than Common Lisp according to the video.

[1] - https://news.ycombinator.com/item?id=6000829