If you went to paper ballots and hand-counting, how would you know whether somebody counted a ballot for one person when it really was another candidate? 150 million ballots is a lot of counting, and anytime people are involved then you have the opportunity for cheating. How many people would that take, and for how long? How many mistakes might be made, honest or otherwise? There are 58 races on my mid-term ballot, and it will take some time to count all of the races correctly and double check them on just one ballot. Suppose a different person is the one doing the double-check; he or she comes up with a different total for a given batch of ballots, what then? I'm not seeing this method as feasible, it's too time-consuming and labor-intensive IMHO. And I think too accessible for fraud.
Now a word about programmer hacking. Some computer systems are closed to external inputs, if the hacker has no avenue to get into the computer then he or she can't do shit. They can be hard-wired and hard-coded with machine code with encryption keys and once installed are not hackable. I'm not talking about the current technology of any of our election systems, they may or may not be all that secure, but they damn well can be. What I am saying is that hackers may be able to acquire somebody's password but it won't do them any good if they can't access the target computer. And that is what our election systems computers need to be. They can be designed, programmed, tested, and fielded with no chance of hacking if it's done right. The key I think is to have different companies and people cross-checking for who did what, to reduce the chances for collusion.
So far as I know, not one of our election computers got hacked, or the data compromised. The problem lies with data entry, people were apparently allowed to input ballots that were not legitimate according to the existing laws, and in some cases observers were shielded from seeing what actually went on. That cannot be allowed to happen again. Even if there are very few cases of voter fraud convictions, when you have nearly half the country with doubts concerning the integrity of our elections, that is truly dangerous to democracy more than anything else.