Preheat oven to 450°. Combine broccoflower and 1/4 cup of the olive oil in a large bowl. Arrange in a single layer on 2 jelly-roll pans; sprinkle with 1/2 teaspoon salt and pepper. Roast at 450° for 20 minutes, stirring once. Add sprouts; roast 10 minutes, stirring once.
Combine remaining 1/4 teaspoon salt, rind, and next 4 ingredients (through capers) in a large bowl. Add vegetables; toss to combine. Drizzle with remaining oil.