Well, I agree the Speedway has it's place but they could update it. Maybe they will but we know they've looked at replacing it. How seriously I have no idea. But other castle parks are removing it, so it's probably not long for the world.
They put in an indoor go-kart track at the Mall of America using electric go-karts. On the surface there's no reason to believe that something similar couldn't happen at MK, although I realize there are more technical challenges to doing something similar outside at the Speedway.