ABRP likes to use roads tagged in OSM as "highway=unclassified" and low "maxspeed:practical" to safe few dozen meters of route. Instead it should use the parallel tertiary roads, which are much more convenient and safer to use. The now disabled beta routing did this much better than the current productive routing.
In the screenshots I have annotated the route I would like to get from ABRP, and which I did get from the beta routing algorithm.
These are the plans I used:
Did a new test drive yesterday. It almost followed the red route, it chose the route over Schulweg, but that is mostly ok. When I did not go that route but stayed on the main road it followed the rest of the red path. So mostly okay now :)
I applied some of your suggestions to the map. Hempbergstraße west of the junction with Schulweg and Schulweg northerly of that have been widened a bit, they now allow two cars to pass each other without going into the dirt. The other roads are smaller.
thanks for reporting. I just looked into this. Correctly supporting maxspeed:practical is not a problem, however the part with Schulweg is not as easy as we would have to add a huge penalty to unclassified roads to ignore it.
So i was wondering if the mapping here is actually correct and we could get this to work better, if we adjust the mapping. All these roads there seem to be very minor roads, almost like agricultural roads, which are normally not public. But here they seem to be (according to OSM). So I was wondering, if it would make sense, to not only tag Schulweg as Unclassified, but also the parts i marked with a red line in the screenshot, which seem to be of same size, quality and appearance from the looks on satellite imagery. What do you think?