There was a big Grease Pencil thread during 2.8 development.
But after releasing of tools in an official release, Grease Pencil users stopped to follow development and spend more time playing with a stable release.
Most of basics are settled, now. Reading release notes is sufficient to stay up to date.
Changing of Data Structure will have no impact visible for users until new tools based on new abilities are developed, in several months.
Currently, most of improvements, done in dedicated branches are about Line Art modifier (that is interesting a niche of people mixing 2D and 3D).
Yiming Wu is working on generating GP Strokes as contours of shadows, cast by 3D objects.
So, that is probably a little bit too soon to try to create such thread.
But if you want to talk about recent development, Antonio added naming of a GP Layer at GP layer creation, yesterday.
https://dev-files.blender.org/file/data/3zzwhbwns2wz7b7fzjkj/PHID-FILE-net5lp2zfzn264adwppn/Move_to_New_Layer.mp4