The softest turning power steering wheels ever I have experienced was in 1991 Chevrolet Caprice Classic - It was called double hydralic power steering.
It was so soft that you can steer it with 1 finger and it will complete a round even after u remove ur finger, hence this feather light steering was dangerous for highspeeds.
On other hand, Honda Accords, 1983-84-85 up to 2000 had this unique technology of power steering, that was lightest on 0 or halt and became harder as the speed increases. The best technology power steerings i have ever experienced.
VW Beetles has good steerings too, i dont know if they came with power steerings or not.
Honda City just have an excellent light steering, but this does not means its a good thing. Corolla is also OK.
Best ever is Honda Accord from 1983-2000, i would rather say in 1989 it was best. I have not driven Accords later than 2000 model.