I don't understand the argument of reducing cost of elections and scaling. The current paper system in place in most works (at least in European countries where I've witnessed the process) and doesn't need to scale more. If actors in a democracy can't afford such a system, and the occasional (once, twice a year) walk to the voting place, 15 minutes wait and fellow-citizen interaction, can't we accept they don't care for voting and participating and stop listening?
I'm all for accommodation of special cases (people with reduced mobility or unability to be in contact with other people) but we already have the necessary systems in place (mail-in or vote delegation).
Literally one of the last places I'd check for change or optimization. It works, leave it alone, I'll happily pay the 3 or 10eur a year.