Poly, I loved your distinction between the grays and the muds.I totally agree with you about the muds, but gaven't yet totally decided how I feel about the grays, like Haunted Heart. I have seen a picture or two of HH that I thought were gorgeous, and yet other pictures of it leave me less than enthusiastic about ordering it.
I find my preference is for closed dome standards. And like you, I like to see some good proportion between the standards and the falls so that the flower appears neither bottom-heavy nor top-heavy. I like the fact that most modern iris have broader falls that are less strap-shaped and droopy. But I do also like flaring falls. Maybe they aren't as easy to photograph, but I love the feeling that the flower is ready to "take off" like a bird or butterfly. Bluebird of Happiness is a prime example, and definitely gives me that happy feeling of flight:
