The antonyms for the word "more stormful" could be "peaceful," "calm," "serene," "mild," "tranquil," "pleasant," "quiet," "mellow," "gentle," and "soothing." These words have positive connotations and imply a sense of relaxation, harmony, and contentment. Unlike "stormful," which is characterized by violence, turbulence, and chaos, these antonyms suggest a more pleasant and comfortable environment or situation. By using these antonyms, you can create a stark contrast with the original word and evoke a different mood or emotion in your writing or speech.