So basically, this is exciting. Say hello to Gaia's theme editor in easy mode.
There are, of course, options in there to add new variants, you can also create a new theme altogether and add variants to it. Each variant has this screen here, where you can tell it what settings to use, what fonts to load from Google, if any, and then set the body and header font families, sizes, set all the colours, and upload a favicon, background image, or banner image, and Gaia will take care of the rest.
I actually *think* I have gotten a little further on handling theme template alteration in easy-mode, so that'll be a cool. (It's still being an asshole, guys, but I'm showing it what-for.)