So many elements in the navigation UX are a similar color.
The worst is the Current route (light blue) and alternate routes (grey). Both of these colors are fairly similar and have very little contrast compared to the background. I have a hard time picking out the difference between a road (grey) and an alternate route (grey, slightly thicker line).
At night, when it switches to a dark color scheme, everything is a shade of dark blueish grey, with very little contrast.