I think a sudden loss of power should be simulated better, if a car in front runs out of fuel I would expect to be able to overtake it without losing a significant amount of time (+1sec in less than 50 meters, both in the straights and corners).
This is the norm and happens all the time.
Why cars can get blocked for so long even though the difference in pace is that big? This is more of a bug fix plea rather than a suggestion.