The pictures demonstrate some of the variation in leaf shape and color. One that is not pictured here was selected for bold leaf markings that show up strongly in the fall.
My favorites are probably the ones that send the flowers up a mast way above the foliage, such as the one immediately below. With my limited skill and equipment, these are hardest to photograph.
The yellow selection immediately above is fantastically floriferous. The pink one above and to the right is a common cultivar, very vigorous.