Antonyms for the word "more rampageous" could include calm, peaceful, tranquil, serene, and placid. These words all represent a sense of stillness and calmness, which is the opposite of the idea of rampaging or chaos. Other antonyms could include orderly, disciplined, controlled, and focused, which imply a sense of direction and purpose, rather than aimless recklessness. These words are all useful in describing situations where there is a sense of control and structure, and where there is not an overwhelming sense of chaos or danger. Choosing an appropriate antonym can help to convey the intended meaning of any written or verbal communication, and can help to create a more accurate and nuanced description of a particular situation.