The word "more onliest" doesn't exist in the English language, as "onliest" is itself a superlative form of "only" and cannot be modified with "more." However, for the word "only," some antonyms could be "numerous," "plentiful," or "abundant." These terms imply a surplus or excess, contrasting with the singularity and uniqueness of "only." Other antonyms to "only" could be words like "inclusive," "comprehensive," or "ample," which connote inclusion and abundance instead of restriction and limitation. It's important to note, though, that antonyms can depend on the context and meaning of the original word, as well as the connotations and nuances of the chosen antonym.