The phrase "most off target" implies that something or someone is not quite hitting their mark. Its antonyms would be "most accurate" or "most on target," indicating that whatever is being discussed is hitting its intended goal with precision. Other antonyms could include "most precise," "most exact," or "most spot-on," which all convey similar meanings. On the other end of the spectrum, antonyms for "most off target" could also include "most wayward," "most inaccurate," or "most off course," indicating that the subject is completely missing the mark.