I looked through Ian's 187 projects on git and still trying to figure out where to start
I can answer the bit for gdemu. Yeah, you can reset it by pressing the button sequences manually. I'm looking for it to be automatic based on a timer when no buttons are pressed for ~five minutes so I get the flashy game intros instead of it being stuck on a character select screen if my friends stop playing. Like an arcade port. And DC has pretty much the whole experience except for "reset".