Asscher cuts in a larger format are wonderful. A 4 carat plus asscher would show the pattern beautifully. I really love asscher cuts. But I feel you need a good size to see the pattern. If she's open to it, asscher cuts are very unique, and have a lot of elegance.
A criss cut or Ashoka style stone would also be worth considering. It has the sparkle a traditional emerald doesn't.
It seems she greatly gravitated towards, Asscher, Cushion, Radiant and Princess. Overall she strongly favored yellow diamonds vs colorless, to be frank im not sure why, she just said that she thought they were more unique and pretty. I do appreciate the immense amount of insight and direction you have given me to help me in this process. It has been a huge help in being able to openly communicate with my SO so I can get her exactly what her heart desires. That means a great deal to me so thank you. Jeremy