Nahh, I say Hang em High!
Well, you could combine the best of both ideas and take her out into the desert, slice out a nice fresh strip of skin off her back, tie it tightly around her neck, and leave her on a fire ant hill out in the sun.
Except we do not want to become that which we most hate and need to punish severely.
Nothing we could do to any of them will approach the horrors of hell, anyway.