[ScotsBrutesFan]

I think the first one is nearly optimised.

What I'd do is keep the kerb between the pit exit and the track going longer, past the turn in point, then have it turn back onto the track.
The point being that not only does the cars on the track see the car travelling parallel with the track for longer and can judge it's speed, but that the car on the pit exit will see in it's mirrors a car approaching.

However with my adjustment assuming the racing line is something similar to the red line. the driver in the pitlane will have that extra few metres to realise that the car on track has run wide or overshot.
The driver makes the decision to enter the circuit, he isn't just blended into an accident.