Blue Spruce and Norway Spruce would be good. But any conifer will need to be caged to protect from deer damage. Not so much eating them but bucks tearing them up in the fall. Bald Cypress is another good choice, is native, and has minimal leaf litter. I would add a couple of Autumn Blaze Maples away from the pond, grow fast, great shade, and great autumn color. Oaks grow to slow. Where about in central IL are you. I have a good source of Autumn Blaze maple in the Mount Sterling area.