More interesting synthlimbs

[Mageziya]

Maybe if you do some splicing you can have the limbs add a small amount of whatever's been spliced in.
e.g. a weed-synthlimb would produce a bit of THC in your bloodstream.

In-before traitorous prion limbs emerge to replace the long dead prion shovels.

Wait, that actually sounds amazing, and also just difficult enough to never occur, ever.