Reading the ballots and resealing them is hard, but reading the names on the ballots and throwing out the ethnic ones, or even looking up party registrations in the public voter registry, or correlating addresses to party affiliation is pretty easy. You'd introduce a pretty big bias using nothing more than zip codes.
It seems like this removes one of the best tools law enforcement has available for combatting the production of hundreds of thousands of images of child porn on the dark web.
A great alternative to this is the app Neutralizer which plays white noise and sine waves while you adjust the eq until the sine wave is barely audible.
My mother is blind and was a rehab teacher. Learn to use a screen reader now, while you can still map the words to the visual structure on screen. The structure applications expose to screen readers is often drastically different than what we intuit from looking at it.
Learn braille. It's hard, resources are scarce, lots of people don't do it any more. This is why, with practice you can read braille off a computer braille display about as fast as sighted people read text. No screen reader can ever be intelligible that fast. Braille is also a much better way to read code syntax.
I'd go with a forehead rest and camera to register facial features position to control for head movement, and just use a vacuum tube/trimmer with some type of length sensor in order to sample length at every 2mm of the scalp, then recreate it at a later time.