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. Switching the governor when executing demanding tasks 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
Edited by Georges Basile Stavracas Neto