I think its better this way for following reasons.
1)The ballot papers are generated on demand(by putting your thumb impression) and it saves millions of ballot papers because using the old method you always have to print ballot papers prior to elections using your best guess, so when there is low turn out there are many many ballot papers which are left without being used.
2)It is more transparent this way, because they could have easily said that they will use a database to register votes, but this way if someone had access to the database could artificially compromise the vote count data, but using this type of technique it will be same as a ballot paper which will later be counted manually.
3)A person will not be able to get two or more ballot papers for the same thumb(and even if he gets multiple ballot papers by playing with the machine then read point 5)
4)When you will put your thumb on the machine it will generate a ballot paper which will contain an encryption code.
5)If someone files a case that the constituency was rigged then all the votes would easily be verifiable since each vote(ballot paper that the machine will generate) will contain an encryption code against a thumb impression. And that encryption code will locate easily who casted this vote. and in case if an encryption code doesn't lead to a thumb impression(a genuine person) you will mark it as fake/bogus vote, and if it leads to someone even then you can programe the machine to locate if any other vote has also been casted by this person, if yes then it will also locate the fraud easily.
But yes i must say that you are right about someone forcing you at gun point to cast vote for him, but this is already happening isn't it? You cannot stop such practice but this type of force vote can account only 5 to 10 percent of total elections, but the greater part of the election can be made secure with electronic voting i guess.This analysis is only according to my understanding. I think things will be much clear once ECP gives its conclusion regarding this system on 31st december.