I'm just gonna keep waiting until the Bevy Editor finally comes out to try and write a game with the engine in earnest. I keep getting ideas but I just don't really wanna deal with writing something as complex and difficult as a game, with my hands tied behind my back any more than I have to.
that said, I'll probably be poking around the ecosystem sometime soon, after reading those updates on the observers in 0.17. They would make big-brain so much nicer to use, and probably simplify the implementation a lot (it would probably be a full rewrite?)