The simplest way is to merely add a couple (or as many as you want) of "waypoints" that guide your routing between your start point and end point. If you want to avoid Atlanta, just click a few points on state highways that avoid the city. I do know that Kurviger (
https://kurviger.de/en) offers you the ability to select the type of roads you want to use, while it computes the entire route. You can pick curves, lots of curves, mult-lane (interstate) no multi-lane, etc. But it can get complicated real quick. Which is why I always come back to Ride with GPS. Click on the map and it draws the route. If I don't like the route it choses, hit the "undo" key and click on the map somewhere else.
