Images are definitely key for a solid PH launch. Eye-catching visuals grab attention right away. I'd also recommend a killer first comment that really showcases what your product can do. Walk through the key features and benefits in an engaging way. Gifs or video previews could level it up even more to make it interactive. The combo of strong images + thoughtful first comment intro has worked well for top launches I've seen.
I think images are the most important for Product Hunt launch as they create the first impression for users. Besides, interactive content, such as such as a well-crafted first comment introducing your product, is also necessary. Personally, I’ve often been drawn to products and learned more about their details through engaging and informative first comments.