I think a good idea for a small addon for the start would be a choice of how the lights came on (set in the options menu). So instead of the countdown, you could have:

All red > All Green
or
All red > Out

Maybe I'm being a bit of a pedant about this, but it adds a bit of flavour now that we have the clutch/false start. To have the lights come on and then change to green in less than 3 seconds would be a real reaction tester, rather than waiting for them all to come on and change.

I've got to say that I'm using the drag strip more than ever now to practice getting away promptly without wheelspin. Thank you to the developers.