We can rebuild it...[3.5 template, PEACH]

[Lysander]

Cyborgs! Awesome! Perhaps they should also get a small amount of resistance to electricity (not because the augmented parts are electronic but because lightning can't hurt those parts as much)?

Perhaps there could be different types of augmented body parts as well, each giving a different weakness and benefit. For example:

Metal Augmentation - Mechanical parts. The creature is harmed by rust spells, resistant to lightning.
Stone Augmentation - Animated stone parts. The creature is harmed by shatter spells, resistant to fire.
Undead Augmentation - Undead parts inserted in their living body. Positive and negative energy can both heal and harm them depending on the intent of the caster.
Flesh Augmentation - Mutated limbs but still made out of living flesh. No benefit or penalty.

etc.