They’re all good ideas.
When I ran elections in the ‘80s we had good ol’ IBM punch cards. They had their problems, like in the Gore-Bush election, but overall they sure were safer. It’s hard to “phony-up” a punch card. When I heard elections people were printing up ballots on a desktop printer, I gasped. (What could possibly go wrong?!)
If you vote in a large venue and blend in you can literally walk out with the blank ballot, scan it at home, make copies, and send the scan to friends who can print them.
You go back to any location, mill about, sit at a booth pretending to fill out the ballot, and then insert it into the scanner.
Without bar codes or QR codes every ballot would be counted. If just one thousand people printed just one extra ballot they would have one thousand fraudulent ballots. Imagine this being done by a coordinated group passing out printed off-site ballots.
Ballots need to be professionally printed with security features that would immediately reject fraudulent ballots when scanned.
That few people recognize this as a problem in mind blowing to me.