The problem with polymorphs is there is no customization once you use one. As seen in your pics, shrikes don't all look exactly the same. I'd rather we get a long hair style, shrike skirt costume, etc. than a polymorph.
More customization options? Hell yeah. Also, I wouldn't mind that hairstyle, which could replace the bra for females too.
What should be the effect of wearing that hair though? Hide chest or tuck inside top? I can’t see it being made to conform to armor so some kind of standard replacer that ends at the neck would be needed. Hats currently do that to hairstyles, with long or short spill out, so it’s not unreasonable.
I wonder if the effect could be achieved by combining a new hairstyle (or head armor style) for the shorter layers and a new chest armor style for the longer layers. I'm not sure if any existing chest armor styles include something like a hood to reference a similar construction and do both at once. It would be fun to wear either way!