Preheat the oven to 425 degrees. Place the fillets on a large baking dish or jelly roll pan. Brush the fish with olive oil and sprinkle with salt and pepper. Place the scallions, garlic, chili pepper, cilantro, mint and tomatoes on top of the fish. Sprinkle with lime juice. Scatter the breadcrumbs on top, if desired. Bake for about 16-20 minutes or until cooked through. If the surface needs browning, place the pan under the broiler for a minute or two.