Rinse and drain shrimp; pat dry. Cut each in half lengthwise.
In a large bowl, mix lime juice, fish sauce, sugar, 1/2 teaspoon chili, and garlic. Add shrimp, cabbage, bean sprouts, rau ram, carrots, shallots, and 1/4 cup peanuts; mix. Taste, and add more chili if desired.
Pour the salad onto a platter and sprinkle the remaining 1/4 cup peanuts over the top.