The phrase "more rockbound" generally connotes something that is inflexible, unyielding, or rigid. In order to find its antonyms, we can look for words with opposite meanings such as "pliable," "flexible," "adaptable," and "elastic." These words suggest something that is malleable, versatile, or bendable. Other antonyms for "more rockbound" might include "open-minded," "creative," and "innovative." These words are associated with being receptive to new ideas or ways of thinking, and demonstrate a willingness to change and evolve. Overall, the antonyms for "more rockbound" convey a sense of openness, versatility, and adaptability.