I drive large trucks and trailers on a regular basis, and in my CDL course we're taught to stick to state roads with a number or a letter, examples: state highway 10, county highway N. If it's got a name we probably shouldn't be on it. There's the button to avoid freeways, but I'd love the opposite as it would be a simple way to do truck/trailer/rv friendly routes.

Even in my personal car I'd prefer it as I prefer cruising over stoping/turning all the time. Also in my experience the state and county highways are usually more well maintained and easier on my cars suspension

No driving app does this and it's missing an entire demographic of drivers