I like grafts too. In my campaign world, grafts are actually symbiotic insects that dig permanent tendrils into their sometimes willing hosts. Neutral, mindless appendages that are bought and sold in shadier markets. Still rare, still objects of fear and revulsion - but not inherently evil.
There are forearm ones that shoot-out deadly stingers as good as any rapier, layered carapaces that provide AC bonuses, and large, lumpier ones that attach to the back to provide sneaky stingers, climbing foldaway legs, or carapace-popping insect wings.
Can't wait to submit them to Varisia's Bestiary!