If you're going in anyway, why vote by mail? Besides, it may show you voted but it won't show how your vote was registered. And you'll clog up lines for everyone else. At least if you vote in person and put your ballot into the machine, that venue of election fraud may be cut off. What you propose does nothing to stop mail in vote fraud.
What if records show you were mailed a ballot? Will you still be allowed to vote? Do you know that for a fact? And, there's a ballot still out there. Will that be returned and "subbed"? Added later for ballot harvesting? Seems a legitimate ballot, doesn't it?
It may be interesting to see if people who do vote at the polls find the registration says they already voted.
I've already and will again check to see that I am still registered- that's another little trick to watch out for.
It would be more equitable if all voting stopped, at the polls and mail in, at the same time. Polls will close while the mail in ballots will go on and on and on…..