The chain-of-custody for paper ballots cast at a polling place (with ID requirements) is the most secure and auditable method. Electronic ballots are less so, but still much better than mail-in (absentee) ballots because they are at least traceable to where they were cast.
Our polling location doesn't require ID. They look up your name in the register, write down your ballet number next to it and have you sign the register. That's it. Pretty much exactly the same as the mail in ballot except the first two steps are done already. No way are electronic ballots without a paper trail better than mail-in. There's basically no audit trail.
The mail in (absentee) ballot was intended for a small number of people with exigent circumstances, such as military deployment, not for those who are too lazy or uneducated to vote. It is the least secure, least auditable method because there are so many breaks in the chain of custody. About as secure as an Amazon package on a front porch of a vacant home. Or American Idol voting.
I'd argue that I was more educated this time. I had the ballet right in front of me and could take my time researching the candidates. I guess if you vote straight party line it's easy (except for Primaries of course), but I don't do that. I appreciated being able to easily look up everyone, on my own time. Previously, I'd have try to find out all the candidates before voting day, do the research and then write it all down and bring it with me.
Also, you can hand deliver your mail-in vote if you don't want to go through the USPS. Really not sure why you think it's the least secure or audit able method.