I'd choose later, even first week of October.
In US cities, the "color" was inconsistent--often still green with some yellow leaves. More color as you go farther north.
Inside the cities seemed to be yellow trees, but out in the country was different. We were the 2-4 week in October, and some places like Maine and Halifax has bare trees at higher elevations, or lots of yellow color but most of the red leaves had already fallen.
Also, we somehow thought we'd see a lot from the ship, but really we'd arrive before sunup and leave about sundown so we could never really sit there an