I've got two that are a beautiful yellow. These look exactly like this in my garden.
Chicago Sunrise
Another picture of Chicago Sunrise
Mary Todd
A light yellow that is pretty, is Big Time Happy. It's too short for me though, and I've sent it to live with my Dad. He said it was gorgeous this year.
Cool it is another one that is light. This one no longer lives with me either, but not because it wasn't pretty. I had to make room for some newer daylilies
Another that I can't find a picture of is Hyperion. It's one of the oldest registered cultivars, but I really love it. It's a very light yellow, and smells wonderful. I used it for hybridizing 2 years ago, trying to pass along it's good smell, and the seedlings smelled even better than it did!