[jschomay]

OP here, cool to see all the similar yet varied testing approaches! Your situation sounds tricky with a real time physics based game. Converting it to step based sounds like it has promise, but as you mentioned, every dilution to the full e2e harness also dilutes the validation veracity. When you were describing your game I kept thinking of Bret Victor's "Inventing on Principles" talk where he "collapses time" in a physics game to render trajectories of objects in all positions at once to visually intuitively tell if it works right. Perhaps that could apply?