x3. Mine beeline for the treeline when I let them out. They enjoy the shade, the extra bit of protection from overhead predators, and the soft soil with rotted leaf matter that's easy to dig through.
I love the shingled area as rain cover/shade.
Instead of the swings, you could put in some sawhorses? It'd give them something to fly up on if they so choose, as well as something to walk around and under.