I pretty much like the way they are in NetHack:
http://nethack.wikia.com/wiki/Cockatrice
Quote
Generally considered to be a real nuisance, the cockatrice, is one of the more complex creatures in the game, and often the source of many YASDs. It can turn you to stone instantaneously if you touch it (or even its corpse) with your bare hands. If, however, you are wearing gloves, you can pick its corpse up and wield it as a weapon, turning enemies to stone instantaneously.
And after all, pecking/biting does mean they have to touch you.
For me, the petrifying gaze thing is more for Medusa than cockatrice, but that's mainly because of hours of NetHack.
Still, it would be cool if her peck wasn't instakill here, the material changing possibility sounds very interesting and would differ nicely from all other games I know.