Marinade: In a small bowl stir together orange juice, maple syrup, mustard, and ginger. Set aside 1/2 cup of the marinade for the salad dressing.
Place squash pieces in a large resealable plastic bag in a shallow dish. Pour remaining marinade over squash. Seal bag and marinate, refrigerated, for 1 to 4 hours, turning occasionally.
Preheat oven to 400°F Coat a large baking sheet with nonstick cooking spray and set aside.
Drain marinade from squash, discarding marinade. Place squash on the prepared baking sheet. Roast squash until tender and lightly browned in spots, 26 to 30 minutes, turning once half-way through. Remove from oven and set aside.
Dressing: While squash is roasting, whisk together the reserved marinade, salt and pepper. Slowly whisk in the oil.
When squash is done, drizzle 2 to 3 Tbsp of dressing over warm squash, tossing to combine.
In a large bowl combine the mixed greens, radicchio and half of the pistachios. Toss with half the remaining dressing. Gently toss roasted squash into the salad. Top with remaining pistachios and goat cheese. Pass remaining dressing at the table.