Preheat oven to 350 degrees F. Mix salt, pepper, chili powder, cinnamon, and garlic powder in a small bowl.
In a large bowl, mix sweet potato and squash chunks, then drizzle 1 tablespoon of olive oil on top and mix to coat with your hands. Add about 3/4 of the spice mixture, and mix again to coat. Lay on a baking sheet and bake for 20 minutes, flipping once.
After 20 minutes, toss apple chunks with remaining spice mixture. Add apple to the baking sheet and bake for another 25 minutes, tossing once or twice.
Let squash, potatoes and apple cool, then add bread chunks to the baking sheet. Bake for 10-12 minutes, or until golden and crispy. Drizzle with a bit of olive oil if desired.
In a large bowl, combine arugula with roasted fruit, veg and bread cubes. Toss with about 1/4 cup of dressing (or more/less) then sprinkle with pom arils. Serve immediately.