Additional Cybernetic Parts?
I'm just throwing these ideas out there.
Add melee skill to character
Add athletic skill to character
Synthetic Dermal Armor
Add tough skill to character
Increased healing ability [not high metabolism]
Synthetic Muscular Nano-Fibers
Add strength skill to character
Neural Transfer / Cortical Array [super expensive]
Makes the brain a "computer" that allows "software" to be downloaded to enhance mental skills like Medic, Electrical, etc.
Yes, some of these are based on Borg implants. :)