They should do a kid or teenage Luke using childhood photos of Mark Hamill as a basis and guide. We've seen him as a newborn infant and a young adult, but never as a kid or teen. Since the Mythos line is supposed to feature things the characters did off-screen/in the Expanded Universe lore then it'd be really awesome to see what Luke looked like growing up with Owen and Beru.
Heck, we got to see Luke's father as a nine-year-old kid...why not his son? And at least Luke won't be screaming "yippee"!