She got the "ears" so I am satisfied, but a bit disappointed with the heels. Sexy? Hell yeah, but not acceptable footwear for someone climbing around rooftops. The high boots look a bit like the Jim Balent design of the character.
Heels to the no.
The only other objection I have is that I'd think loose hair would be a liability for a cat burglar. Hopefully it'll get tied down or something.
Ear-goggles work for me, and there is sheer elegance in the costume's simplicity.