My thoughts on the design:
If I was thinking of "Romanticized" "Civilized" Romanesque culture for the background of Superman. With Aquaman I went the other way and thought of a more "Gladiatorial" inspiration. I can just imagine the deep sea to be a very dangerous place, so Aquaman really needs to look tough.
I maintained Aquaman's color scheme, just made it more battle ready, but still invoke Royalty worthy of the King of the Seven Seas.
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-access out, God speed
Read more about Aquaman in my site here