Hiya there, Sly! (Can I call you Sly?) I’m the one who suggested you move your post over here.
To start, here’s a few threads that might have some insight to what you’re asking. You can read them in the meantime while I tag some of the more frequent authors who are on the forums.
Keep in mind, I think these are geared toward being a Hosted Games author, which—if your soliciting email isn’t accepted—is pretty much the only other path to getting published through them.
Tag City
@Eric_Moser @Cataphrak @HannahPS @malinryden @Havenstone @Gower
Sorry if I forgot anyone! And WIP authors feel free to reply! There’s just a limit on how many people you can tag in a post, lol.
Again, I think this is only true for mainline Choice of Games. Hosted Games has a lot more creative freedom.
As @hustlertwo pointed out, no one is writing exclusively for CoG or Hosted Games and doing it full time (yet), but Patreon seems to be a way to definitely supplement your income, provided you have a large enough fanbase.
Now, you can’t offer free versions of the game when you’re finished, but I believe you can offer a beta version of the game for certain tiered patrons to test.
What a lot of authors do instead is offer short side-stories or—if they’re artistically inclined—artwork!