The antonyms for the word "more hard-shelled" could include words such as soft, delicate, pliable, or malleable. These words all suggest a looseness or flexibility in texture, the opposite of the hardness associated with a hard-shelled object. Another antonym could be vulnerable, which implies a lack of protection or defense, further highlighting the stark contrast with the idea of a hard, protective shell. Ultimately, the antonyms of "more hard-shelled" present a range of words that highlight the opposite qualities, from softness to vulnerability, that are not typically associated with hard-shelled objects.