I find myself always going against Waze’s route on my daily commute, because it suggests taking the highway right at the start of the journey, instead of going a bit by the main road until the next city and then joining the highway. This happens because the highway is the fastest route, but the other option is just 4 min extra time in the morning and saves 2 euros in tolls which is half the cost of the journey, if I would take the 100% highway route.
There could be a feature, where I could say how much 1euro should save me in minutes, could be done with a slider, in the configuration where you chose to avoid tolls or not, and this could be active or not.
This way I could say than 1 euro needs to save me let’s say 10min, and the algorithm will check if the alternative, the main road, is longer than the minutes x toll cost of the equivalent section.
Of course this should only happen one time per highway stretch, meaning that it won’t make me leave and join multiple times to the same stretch of highway.