GNOME showcases a number of possible GNOME Shell changes
The GNOME Shell user interface has mostly seen minor refinements and quality of life updates in recent cycles, but on the design side we've explored a lot of longer-term things we'd like to do. Some of these we have relatively complete plans for, others are more vague ideas that need more research and prototyping. As always, getting things like these implemented depends on developer capacity and interest (and sometimes funding).
While each of these ideas may require additional discussion, prototyping, and testing, we (the design team) have collected them all together here to share our longer-term vision and to give each idea more visibility.
Tobias Bernard on the GNOME blog
There's quite a few good ideas in there, with most of them already being available in the form of various extensions. I'm not entirely sure if I'm a huge fan of copying Android and iOS by moving notifications into the quick settings dropdown thing, but it's not like having them in the clock/calendar dropdown thing is any better. I only use notifications as they arrive and never look at the place where they end up - that's a mobile thing for me - so I don't think I'll really care either way.
Things like editable quick settings, transparent top bar on certain backgrounds, the improved window drag and drop in the Expose view, the alt+tab experiments, and some of the others do seem quite interesting though, and anything that reduces the number of GNOME extensions I need to install and keep updated gets a big thumbs up from me.
If you wish to work on any of these suggestions, working on GNOME Shell has gotten a lot easier recently.
In the past, GNOME Shell was significantly harder to contribute to and test than apps since you needed to use tools like jhbuild. This has changed in the past year: You can now easily build and test your branch in a nested session from Builder using Mutter Devkit. If you use GNOME OS, you can even build a sysext to install your branch on your host system. This allows daily driving experimental branches easily, which is super helpful for evaluating changes to everyday workflows.
Tobias Bernard on the GNOME blog
That's quite neat.