Following a second day of listening in the car, I think I've fixed many of the tracks with obvious problems, and have a near-final mix on 9 tracks (which is exactly half of the album). Next time around I may want to take a voice recorder so I can record notes while I'm driving.
Of course, I'm neglecting other parts of the project, like uploading rough mixes so that people who've preordered can hear them. Tomorrow?