This is a great design, very smart construction! The only modification I made - skipped the last stripe and made the hem wider, to even up all the stripes.

I used:
Grey – 407yards/372m
Yellow – 379yards/346m
Green – 362yards/331m
Brown – 456yards/417m

I love Anzula Haiku, but for this cardi I would suggest yarn with no bamboo/nylon, something that would keep the shape better. But it is soooo soft:)