So I think the chromatic dragons in Dungeons & Dragons are pretty much perfect. I don't think they should be staggered by difficulty-- I don't like them being ranked from red to white, & would rather they just filled different roles, like in 4e, with brutes & artillery & what have you-- but otherwise they are pretty great. Unique habitats, it's easy to remember who breathes what, it's cool that they have different breath weapons, & Tiamat rules. It's a nice paradigm & I think about the also-rans, the metallic dragons & the even less well known gem dragons. Years ago, I wrote about Apzu, who is my "missing sibling" for the colours not represented in the chromatics; purple, orange, yellow. I've revised that in my head to cram in gem dragons. Amethyst, Amber, Topaz, there's our neutral psionic dragons, the children of Apzu, a dead draconic god. (I've also had an idea that purple worms are the failed purples, rust monsters are failed oranges, but can't fit the two puzzle pieces together, yet. I thought before about linking their breath weapons to that-- rust dragons are my favorite non-standard dragon by a wide margin-- but that's just stuff to brood on).
With the metallic dragons, the "good," dragons, I've always been pretty annoyed at what a hodge-podge of too-similar metals were used. Brass, bronze & copper? That's...those are all copper alloys. What's the difference between which? Who breathes what, & what do they care about anyhow? Coppers have lightning, that's clever, & they are the...funny ones? I think. See, I don't even know, & so here is my fix: why not associate their colour scheme with historical or mythological paradigms? Just go ahead & cheat. Brass dragons, why they can summon genies & bind devils & live in desert climes because they remind me of Solomon & Arabian Nights. Bronze just makes me think "Bronze Age," so why not go ancient world? Golems of the statues of far antiquity, stone tablets of cuneiform & hieroglyphics & mysterious Linear A & B stuff. Copper dragons are the reverse, scaled Ben Franklins or Isaac Newtons, they love The Enlightenment & electricity & "high tech" treasures. Gold & silver you don't really need to mess with, & I would probably throw an "iron dragon" in while I'm at it. (Illustration by Wayne Reynolds.)