The phrase "down at the heel" refers to someone or something that is worn out or shabby. Some antonyms for this phrase would be "elegant," "refined," or "luxurious." Another antonym could be "polished," meaning that something is well-maintained and in good condition. "Upscale" and "high-end" could also be considered antonyms, suggesting a level of quality and sophistication rather than decline or neglect. Additionally, "dapper" or "impeccable" could be used as antonyms, indicating a sense of neatness and style. Ultimately, there are many possible antonyms for "down at the heel," depending on the context and the specific qualities being contrasted.