I thought I saw traffic displayed in the navigation view. Can't see it now because I'm at home on a country road, but I think I remember it showing up when Google has traffic information.

I just discovered how to toggle between time-to-destination and arrival-time: just tap whichever one is displayed and it'll switch. I'd give that a thumbs-down for discoverability but thumbs-up for usability once you find it. The way this worked in the old version was another weakness: it showed time-to-destination in the navigation view and arrival-time in the route view.

[Edit] Playing with the app here in my home office, I can see it has some nice features. It just doesn't look ready for release.