Thanks to Martin Cowan:
“While not a huge fan of the official Basement Tapes LP and as someone who hasn't really heard all that many of the unofficially available tracks, I'd certainly welcome an official release along the lines you've suggested.
“BUT I would have to say "no" to overdubs. I would suggest that part of the magic of the Basement recordings is their "lo-fi" nature and that in fact this unique sonic atmosphere makes up for the shortcomings in the performances and songcraft.
“If some of the stuff is so lo-fi as to be not worth releasing in its raw form, I guess that’s an argument for not releasing it. I'm not a big fan of dubbing historical recordings.”