Nuclear liability is a very important question.
But for starters it has been relatively a safe way of producing carbon neutral electricity other than the Chernobyl and three miles island reactor failure .Harm to environment has been small and benefits tremendous.France has produced electricity with a good safety record.
I do not know how the figure in India was capped at 450 million dollars .What is the limit of us plant liability and the liability in European countries.That should help India set its liability limits.
Their are for sure ways to design safer power plants and add safety measures which can reduce the liability and its costs .All the nuclear powers have tested nuclear bombs underground as well as above ground leashing the full effect of the nuclear weapon that is much more than any accident.
Installing nuclear power plants away from population can also help reduce damage because of accidents.The other rule of thumb can be excess liability insurance to be sold by Government of India and its institutions certifyng the safety of the powerplant design and operational safety.
Help of the companies like FM Global can be taken to design better plants as they have lot of experience in loss mitigation technologies.