We keep suckling on Cities: Skylines news teat, because a) it's good (opens in new tab), b) it's doing well—having just broken (opens in new tab) the 500k sales mark—and c) it has mod support, and so has a community that's consistently pumping out great stuff.
For instance, right now on the Steam Workshop you can find a couple of buildings from Bryan Shannon—a former Maxis (opens in new tab) employee who worked on both SimCity and its expansion, Cities of Tomorrow.
Whatever you think of SimCity—and I know what you think, I have read the internet—it was a beautiful looking game. That's reflected in Shannon's buildings, which fit nicely into Skylines' aesthetic while experimenting with its look.
"Overall, this coal power plant is a deviation from the original style," writes Shannon of his coal power plant (opens in new tab). "This asset introduces a nice dirty brown brick in to the game's overall neutral palette."
You can see Shannon's Skylines buildings here (opens in new tab), and see the work he did for SimCity over at his blog (opens in new tab).
Update: Shannon is now on Patreon (opens in new tab), taking pledges to fund his work inside of Cities: Skylines.