Thanks for the suggestion. We'd be more than happy to create a sandwich board but the end user has to do the weight painting and parenting of the board to the character model of choice. We'll certainly provide some custom sandwich board templates as upcoming additions in the "Free 3D Assets Collection" along with some belts/attachments soon. You can integrate them into your character models depending on the requirement.
Feel free to contact us here if you have any queries or suggestions. Have a great day ahead.