Add UI View Options to Preferences
The new compact design is great as an option, but users should be able to toggle it on and off. Gmail calls this “Display Density” and they give you three options: Comfortable, Cozy, and Compact.
I bring this up because the compact design is not ideal for large screens (e.g. Ultrawide monitors with a 21:9 aspect ratio, or even just monitors with a normal aspect ratio and a large footprint like 25”+)