There was a brief time where cowboys and samurai coexisted in our time.
So you don't have to keep it "Western" (as in european), you can also add "Eastern" (as in asian) influences. (Adding those dragons into the mix could add another dimension)
But all this talk about "hidden" dragons also got me thinking in the direction of "Dark Sun".
Dragons, once bound to/manifesting as mountains or rivers "discovering" greed from the minds of newcomers, spiraling out of their self imposed bounds and try to expand their influence, maybe be increasing the reach of their minions by railways - some of them even cutting through the "bodies" of their opponents (corrupting them too)?
The Earth/River/Shadow dragons from A5E fit this way quite well and you don't have the problem with the "good/evil" dragon distinctions
Largely true. Except that Shadow Dragons -are- Evil entities.
That said. I could use those three essence dragons as a basis and describe the Shadow Dragon as a Soulless dragon to place it firmly into the position of capitalist imperialist greed?
Could even go straight Ferngully with it and have some of the immigrants awaken a long-dormant dragon that was kept contained since time immemorial underneath the Acadian range of mountains... in fact... I know a great place to put it...
The equivalent of Centralia.
If you don't know, Centralia has absolutely massive coal reserves like much of the area on and around the Appalachian mountains, since the trees and plants that grew and died, there, existed -before- decompositional bacteria evolved to break them down. We're talking -millions- of years of trees dying and not rotting. They'd just fall over, dry out, and lay there. Undisturbed by anything but wind and the occasional thunderstorm setting forest fires in scopes the likes of which humanity cannot conceive.
In Centralia Pennsylvania in 1962 one of the mines caught fire. And it's been burning ever since. Right under the feet of the residents for decades on end.
What if the great battle that shattered the peaks of the Acadian range was a battle to contain the last true Shadow Dragon? An entity of greed and corruption, torment and cruelty... unleashed by greedy fools who did not know the danger, did not heed the warnings, and delved to plunder resources they should never have taken.
A Railroad company, mining coal for its hungry beasts, awakening a terrible evil that takes control of their interests and enslaves their people to manifest its own greed, its own interests, at the expense of everyone and everything.
And now the setting has capitalism, imperialism, and environmental devastation as core political themes! I love it!
Could even have River and Earth dragons about the lands who oppose the Shadow Dragon and help mortals to build resistance movements against it, even though they dare not oppose it directly or they, and all they can offer to mortals, would be destroyed.
Ooooo....
Could add the dangers of Isolationism into the mix by having a large number of Earth and River dragons be unmoved by mortal plight. Unwilling to lift a talon to help them... At least until they, -themselves- are threatened by the Shadow Dragon's machinations...