Meanwhile, in large skillet, heat red pepper flakes, remaining garlic and 2 tablespoons oil on medium until sizzling. Stir in wine and simmer 1 minute. Stir in orzo to coat, then tomatoes and their juices, crushing with hands, and 1/2 cup water. Simmer, covered, stirring occasionally, until orzo is just barely tender, 8 to 10 minutes. Add shrimp and cook, covered, until opaque throughout, 3 to 5 minutes. Sprinkle with parsley and feta.