Photos should look authentic, engaging, and not overly produced like stock photos.
Location
Use photos that feature different areas of Washington state. Avoid looking too western Washington-centric.
Plants and animals
Use photos of native species as much as possible.
People
Use photos of people interacting with nature. Avoid the "outdoor enthusiast" aesthetic. Nature is for everyone: casual strollers in the park, gardeners, kids in a playground, etc.
Use photos of people in political/advocacy settings.
Use organic shapes to crop photos to avoid the harsh edges of squares and rectangles. Add a thick border around the photos to bring in additional color.
Download organic shapes using this generator site: https://www.blobmaker.app