Remove images not related to (or contradicting) your story eg. images of people sun-tanning when you are promoting cold water wetsuitsImage size is optimized (tool: ImageOptim)Infographic images and logos are optimized for Retina screensBackground images are not clashing with copy (ref)Image alt tags set to describe image if media is disabledIdea: Add drop shadows behind the images (ref)Bonus: Do your images add personality? (ref)Poor images? Consider pivoting to illustrations (ref)Advanced: Images tell your product or service story on their own. If you removed all Landing Page text, would your visitor know what your offering does?