The antonyms for the phrase "more old hat" are modern, cutting-edge, trendy, innovative, and newfangled. These words signify something innovative and advanced, which deviates from traditionalism. For example, a traditional watch with an analog dial and leather strap may be considered old hat, but a smartwatch with a touch screen and advanced features would be considered modern. In the world of fashion, vintage clothing may be considered old hat, but current fashions with unique designs, bold colors, and new textures are considered modern. So, while old hat represents something that is outdated, antiquated, traditional, or conventional, the antonyms represent contemporary, new, and innovative things.