In the Library you can find routes based on where they start, but I think people are not really interested in that.
What people are mainly interested in is a route that starts e.g. within a circle of 25Km around a place/town/city to a place within a circle of 50Km around their destination. If people are gonna use such a route, the will adapt it to suit their exact starting point and destination anyway.
So my feature request is to make filtering on starting point withing X km circle and destination within Y km circle. That way you can keep increasing parameters until something suitable shows up to base your own route on.