On the current fist? Nowhere I can think of. On a new hand piece? Probably the palm. Imagine a hand piece without fingers that has a bar for things like Exo-Force arms to clip onto to serve as fingers and thumb. It has a pin or axle hole through the palm for weapon attachments. That's the dream hand right there. thought a doodle might be relevant, since that's my thing: yes? no? idk, kinda a mix concept of the current fist, a y-socket, the beast foot, and the droid torso, has a hole all the way through the palm and a hole on either side to attach a thumb-swivel assembly, could use chima claw, exo-force arms, or some new skinnier finger? Pros: is detailed, poseable, probably scaled a bit better than current custom styles Cons: might be too fragile? probably adds too many pieces for smaller sets to use (five parts a hand) I've been thinkin' about something like that for a while. Thanks for drawing it.