Joyfull ride
I'd like to propose this idea for waze, I'd call it "Joy Ride."
In this case, I would like to choose routes with curvy roads, other secondary roads, and not too slow speed limits.
Yes, I know what you are thinking, why don't you just use the feature "avoid Highways"?
But the problem is that if you use these features in some areas, it just diverts you through streets full of traffic lights and limited to 50 Km/h, not too joyful if you ask me. When what I want is to use the highway until I can divert to have some fun.
There's also the case in which you want to have a joyride, because you have time, but you still want to get somewhere. So constantly choosing secondary roads can be too long, but choosing one or two would be fine. I don't know how to exactly implement this, but maybe waze would choose the usual main line and then propose detours or alternatives that you could select before leaving.
Hope you find this idea useful.
Kind regards,
Adrià