I just want to point out that all of the issues you point to with Manual Voting in the US are nothing to do with Manual Voting itself, and are entirely down to US Politics. In no other country where Manual Voting takes place are there the massive lines that are seen in the US, nor the Problems with counting, and other issues. Look at India, over a billion people, at least half of which can vote, and they dont queue for more then 30 minutes. Same in Australia, Germany, even in the UK.
US Politics have made the problems in the US - onerous ID requirements designed to suppress certain sections of the voting population; reducing the number of locations where voting can take place; voting taking place during the week instead of on weekends or holidays, such that those who are working and cannot get time off cannot vote. All of these are byproducts of US Politics, and nothing to do with Manual Voting.
And I'm afraid, your suggestion of Electronic Voting, wouldnt fix any of those problems. Those without electrical devices (the elderly and poor for example) would automatically be excluded (voter suppression once more). ID requirements would likey remain and would probably require you to either visit or send off those details to some government department, not making it any easier for the sections of society currently suppressed by such measures to vote. Additional requirements would likely be added so as to continue to suppress certain sections of society, if Electronic Voting took off. Time frames for voting would be closely controlled to limit voting by those deemed undesirable by the ruling party. I'm sure you can come up with further voter suppression techniques that could be used to continue to suppress "undesirable "voters.
Before Electronic Voting will make the US more democratic, you would have to fix US politics first - gerrymandering, the electoral college, that all 50 state have different voting rules - these are all failures of US Politics. The choice of Manual Voting or Electronic Voting will fix none of those.
Manual Voting works. It's proven throughout the West for a 100 years and more, that's why it's used. I'm glad Estonia are using Electronic Voting and works for them. But all it would take is one large failure, a hack, a changed election result, and confidence in that system will fall. Manual Voting requires an entirely corrupt system in order to fail, and by the time you've already reached that stage, (hello Belarus), the voting system, whether Electronic or Manual, is not going to fix anything. Plus it is easier to film bags of corrupt paper votes being carried into distribution centres, then to see a single changed value in a million lines of code.
I know which one i trust...