I had another test-drive and you are right, the auto recalculation of the route is good, I prefer it to many other devices because it seems not to start with trying to redirect you back on the original route but right away finds a new route (at least that was my impression during testing).
Nevertheless, since you need a certain distance to trigger this auto recalculation there are certain situations especially in navigation in cities, where I still would prefer to have the additional option to manually trigger the recalculation (you could add an additional button in the menu of the options button of the navigation info-section on the left)
Example: A city with lots of long one-way streets, you did a wrong turn and are now at the next red light and need to make the decision how to get back to the track but the direct way is a one-way street in the wrong direction – you’d really appreciate the button to start the recalculation of the route from the current redlight (still red) rather than go straight froward over a bridge and ending up on the wrong side of the river on another one-way street where there is finally enough distance to trigger the auto-recalculation. Situations like this actually happen quiet often, and usually (also using TomTom or all the others) I stop by the road, end navigation and restart navigation to the last destination – so I really miss that button in all the navigation systems/apps I’ve been using so far.

By the Way:
A List of recent destinations as well as preferred destination (like home, and other favorite spots) would be nice to have