Following Birger T suggestions here is another expansion having the arms to the front, including a new grip design for you to 3D print. Do you want them for for boxing :D? Note the clip on the back is for the Bluetooth module ;*

Legs you can use Ottoky ones alternatively. they are outside the body without elevating the center of gravity

Next will be the OLED display as alternative to the LED matrix but there are memory limitations for it... how are we gonna solve that?