Cooked quinoa, millet or lentils can be subbed for the rice. You can also use part grain/part chickpeas. Or omit the tomatoes and basil and use different quick-cooking vegetables like thinly sliced fennel, diced zucchini, shredded carrots, blanched cauliflower florets, peas, scallions. And use different ingredients to add in later, such as cooked beets, sliced oranges, avocado, olives and so on. There are unlimited combinations!