"On skids" is an idiom that generally means "in decline" or "in trouble." Antonyms for this phrase would include "prosperous," "thriving," "flourishing," "stable," and "successful." While "on skids" may imply a negative situation, these antonyms convey positivity and success. For example, a business may be "on skids" due to a lack of profitability, but it can become "prosperous" by implementing new strategies. Similarly, a person's life may be going "on skids," but they can still turn it around and become "successful" in their endeavors. Overall, these antonyms provide a contrast to the negative connotations associated with "on skids" and offer hope for a more positive future.