[protomyth]

Probably easier than open road, but the surface is a constant problem. NASCAR for example runs multiple races at some venues where the spring and summer races act totally different. Some of the differences are heat, rain between practice and race (rubber on track difference), different tire formula, possible resurfacing, and changes to rules (aero or engine).

Restrictor plate racing with a computer car mixed in would be extremely interesting. NASCAR does not allow telemetry, speedometers, or fuel gauges. This would make for an interesting computer car in these parameters.