The only problem with weekend elections is that they'd likely run afoul of religious observances. I'm not sure I want people attending a church for services the same day that a polling booth is open in one. And if we went Saturday instead of Sunday, would that be a slight to the Jewish?
I dunno, I sort of like the Tuesday tradition. A better solution would be to make "Election Tuesday" a national holiday instead.
And don't forget idiot football fans that will forget to vote due to watching their team play on Saturday or Sunday