Would it be possible to implement a means of comparing a driver's actual performance in a heat or practice with his ideal performance, based on his fastest lap? In other words, could you count the amount of time a driver spends on a lane and divide that by his fastest lap time to see what the ideal number of laps could be, if the driver had driven every lap at the same (fastest) time? If you could compute that number, you could compare it to the actual number of laps completed, and derive a percentage "efficiency" rating compared to the driver's ideal potential.
I'm hoping that description is clear enough. I think this would be a great addition to the program to help drivers improve during practice. If you created a specific "efficiency" race type, say a 5-minute time-delimited practice, you could just use the same algorithm to compute efficiency at the end of that 5-minute period.