For now, I've finished painting the GQ Gyan with ceremonial intent in mind.
I left the base pure white and went for a somewhat subdued tricolor of blue (pearl light blue) and gold (titanium gold), but the shield somehow looks like a parasol...
I've removed the decals because I plan to decorate it with gold stickers from here on.
However, while the Gunpla itself is of incredible quality and fits beautifully without any stress, posing and photographing it is hopelessly difficult (for me, Hakuji).

GQ Gyan ceremonial paint job completed | キャトル's Gunpla works