To get TBT on the roads you wish to travel, the easiest thing to do is to put route-points on those roads each in succession. If you do not do that, the DEVICE itself will create the route for you, based upon what criteria has been setup (road, cycling, walking, etc). Some newer GPS units designed for motorcycles have "curvy roads".

Way back when Zumo 550 was "state of the art", I designed a route for a trip in WV. I had to put a route-point on each of the roads I wanted to travel. Otherwise, the GPS calculated the "fastest" route.

I do not know (yet) if the EDGE 1030 I have will give me precedence to bike paths or not. As indicated by njkayaker, I use RideWithGPS to route my rides. Once you figure it out (tutorial OK, but not sufficient), it works well for street and off-road trails. Then it is easy via Garmin Connect to DL to the EDGE.