The word "more fouled-up" implies a situation that is already in a mess or disarray. Its antonyms, therefore, would be words that indicate a state of organization, clarity or harmony. Some possible antonyms for "more fouled-up" are words like well-organized, streamlined, neat, tidy, uncluttered, systematic, arranged, sorted, refined, structured, and harmonious. These words depict a state of orderliness that is the opposite of chaos, confusion, or jumbled-up situations. Using these antonyms in your communication can help to convey a positive message about a well- managed and structured situation.