Combine first 8 ingredients in a small jar. Cover with lid; shake well.
Combine chickpeas, quinoa, and 2 tablespoons dressing; toss well.
Arrange 1 cup spinach in each of 4 quart-size containers. Top each serving with 1/4 cup blueberries, 1/4 cup tomato, 1 1/2 teaspoons sunflower seeds, one-fourth of avocado slices, 1/2 ounce goat cheese, 1 1/2 teaspoons mint, and 1/2 cup quinoa mixture. Cover and refrigerate until ready to serve. Drizzle each serving with about 2 1/2 tablespoons dressing.