There are hairstyles and rubber band in the game, so why not use it?
For "Tie Hair for ..." to PonyTail/Bun/Back - require Rubber Band in inventory, and if "Untie Hair", then the Rubber Band will return to inventory.
To make such trifles in mod is not serious, it is better to include in the main game.
There are very few changes in the code (see here), and it will look good together with the addition of makeup.