I was at Yahoo when they did a big email redesign, and the new design didn't work for 1/2 their users. Digging deeper, they found that email users kinda fall into 2 camps: filers and pilers. Filers carefully organize their data so they can quickly navigate to their target. Pilers just collect stuff in a big pile and use search to find their target.
Sounds like you're a filer (I am too). Sounds like emdash is kind of a mix of filing and piling.
I don't know about "hero" use cases, but I use actors (state machine responding to events in a queue) quite a bit when making hobby Arduino devices. It allows me to have a "button" device that can work with both the hardware pin interrupt controller and a clock to generate "click" and "hold" events, to pass to other actors in the system. I also will also use an actor to manage an I2C device, so that that actor can detect errors and restart the device to recover from errors. You could do either of those things without actors, but doing so has made it easier for me to compartmentalize my code and organize how data flows and states change.
Sounds like you're a filer (I am too). Sounds like emdash is kind of a mix of filing and piling.