I think the Ex- Nadra Chairman Tariq Malik Electronic Voting system was way better and least rigged system. Since his system would only generate a ballot paper after verification of CNIC. And then you will have to manually choose a candidate and put that Ballot paper in the ballot box.
The machine would not generate a ballot paper for a person who doesn't have an ID card, and also won't generate a ballot paper for someone who has already voted. Similarly if there is accusation of rigging. The record of the Ballot papers(which contains a special code) can be cross checked with the Nadra Data base easily.
So Tariq Malik System was way better than any other system..