[feature] Power profile (governor) selection
A low-power mode is an almost essential feature in any OS "control panel", but currently extensions are needed to have this functionality in GNOME Shell. Having some minimal power settings that switch governors for casual users would help.
One of the best designs I've found is the slider-based one of Lineage OS: https://www.xda-developers.com/files/2018/02/LineageOS-15.1-Battery-Saver-and-Performance-Settings.png