The phrase "more meat and potatoes" is often used to refer to something that is substantial and important, but sometimes we need to express the opposite of that sentiment. Some antonyms for this phrase could be "light and fluffy," "flimsy," or "insubstantial." Other options could be "superficial," "shallow," or "trivial." Additionally, you could use antonyms that emphasize a lack of importance, such as "unimportant," "trivial," or "meaningless." Ultimately, there are many ways to express the opposite of "more meat and potatoes," and the most effective antonym will depend on the context in which it is used.