I’m not sure that this is a “game” idea so much, but I’ve had this idea I haven’t been able to wrap my head around the implementation of.
Think a digital audio workstation such as Ableton Live or Logic, but gamified. Complete various musical objectives to pass levels, have a creative mode for just making music and maybe even a multiplayer mode for collaborative or competitive music making.
I am just now starting through Fallout 4. I’ve had it in my library for a while but never got around to it.