Great work!

Just an idea, would be nice to run tint-overlay as a daemon that enables on sunset and disables on sunrise automatically (as an option) like gnome-shell night mode

Could be calculated based on GPS/Glonass or manual entering latitude and use this formula: https://en.wikipedia.org/wiki/Sunrise_equation (https://ru.wikipedia.org/wiki/Уравнение_восхода)

Have a nice day!