Rita's Upper By-Pass is a good introduction of practicing rock navigation and line choice. It starts with a gradual climb before dropping in and out of a ridge. It then skirts the side of the hill, going in and out of its ridges. Be prepared to power out and stay high on the trail to not fall off the trail.
It then goes into the hill one more time before a test of rock skills presents itself. Going west, the trail goes over exposed rock. It then descends a fun rhythm section before ending at a junction that carries out the speed to the west.