Reconsider background vignette
Global dialogs (like the shutdown menu and authentication prompt) and the overview use the user wallpaper with a darkened vignette effect as background.
In my opinion, this effect is a bit too much, and a solid darkened background color would fit the design more. A solid darkened overlay would look simpler, make text easier to read on the center of the screen and fit the design better in general.
I'm interested in the decisions that lead to implementing this vignette effect, and if those are lacking, would like to see a reconsideration of this design decision in favor of a solid darker overlay.