It seems to me that you really need to capture some basic use cases to help define what a user may want to do here. I can put a couple here so folks can see what I mean:
Use case 1: Planning a vacation trip User wants to take a multi-day driving trip, via a specified route (e.g. along Route 66 in the US). During the trip he wants ETA to the next waypoint as well as directions.
- User starts Navit.
- User enters starting location (Adams St. and Michigan Ave., Chicago)
- User enters next main waypoint (Joliet, Il.)
- User repeats for whole route (MANY waypoints).
- User reviews route.
- User adds additional routing points as needed to stay on Route 66.
- Until plotted route matches Route 66.
- User saves route to disk.
- User sets out on route.
- User asks Navit for ETA to next waypoint.
- Navit reports via speech synth.
- Navit provides nav guidance.
- A road is blocked. User requests re-route.
- Navit computes alternate route to next waypoint that uses a different road than the current route.
- User takes wrong turn
- Navit provides new guidance to next waypoint.
- User stops for the night and shuts down Navit.
- User starts the next day, starts Navit
- Navit loads current route, computes where on the route they seem to be, selects next active waypoint.
- Alternate: User selects which waypoint on route is the next waypoint.
- User decides to take side trip.
- Navit offers navigation advice to get back on route.
- User tells Navit to suspend guidance for a while.
- User completes side trip, re-enables guidance.
- User (eventually) gets to end of Route 66.