I'm still in awe that you were able to get those patterns so beautifully symmetrical... (or like that saying for eyebrows, 'they're not twins, they're sisters', lol) Your sense of light and shadow and your ability to define different kinds of materials (especially the opal!!!!!) is really remarkable!
Do you plan on filling the moons out with the badges he gets?
For symmetricality, I just kept turning my sketchbook for each curved pattern addition.