Why has no one thought about making a Scalectrix video game before? Great idea and also incredibly fun, I'll definitely come back to replay this one! Only suggestion I have, which you've probably thought of already, is make it so that it's also unsafe to go too fast or you risk running off the road, like with the real thing, perhaps with an incremental throttle somehow and maybe a speedometer/throttle meter? Edit: Come tot think of it, the obstacles and the intersection is probably challenge enough.
Also MP support for this would be really fun, reminiscent of that super-fast Micro Machines racing game from way back when.