Further to my post on the "fast charge" quick setting button, I thought that a more elegant solution would be to just add a fully customisable option for quick setting buttons.
In this menu the user would be able to apply any setting in the phone to a customisable button in the quick settings menu. They could then name it, and designate an icon of choice, or select a generic one.
For example, the hidden fast charge selection could be applied to a custom button and added to the quick settings menu under "fast charge", or the battery protection option could be assigned under a custom button called "battery protection". Samsung would not longer need to code a particular option to a particular quick setting button, the user would have full control to make their own.
You could also allow for a value to be assigned. I.E, if the user wanted a quick setting for 10% screen brightness, or 40% etc, the button would apply this level. This could be used for volumes, or screen warmth options as well.
You could even make the quick setting button have multiple functions rather like a routine; at bedtime you might opt to have a low screen brightness say 10%, mute the phone, turn off battery protection, and set the alarm to on, a quick setting button to do all this would be a very elegant solution.