The default yellow (or non-human) skintones are a great feature of the emoji spec. A vast improvement over default white for sure, but it isn't realistic. It simply avoids the racial diversity issue.
If you would like to bring race back to your emoji in an impartial way, install this extension.
Download from the Chrome Webstore
Bug reports and patches for bugs are welcome, but this extension is more or less feature complete. I am not accepting feature requests.
./bin/build.pyThis will save a emoji-support.js file in ./bin. It will also inject that file into postprocess.js and options.js.
Now you can add the ./dist directory as an unpacked extension in Chrome and start hacking.
Fist logo composited from Emoji One assets.