In terms of modeling I'm sure you're right. Something about Hard Drivin' makes it feel not like a straight up racing game. It was an odd combination of physics + disembodied stunt tracks.
The combo of a sim, but a playful environment seems very hard to find.
I see your point, maybe something like BeamNG.drive when it is finished.
Spiritual successor? In terms of realistic car modeling, I would say the rFactor series.