I'm glad you like my idea, but that's not my art. I just responded to your question. I'm not the artist, just a fellow viewer. Also, GW might not go for a different model of carapace armour when the Imperium is technologically-stagnant, because of the lore and maybe because it'll be harder or more expensive to produce more models for various vanity-pieces. If the artist wanted to do it, he could, but he should be ready for rejection for canon art.