Great job! I've wanted to do this myself, and I'm kind of surprised Hasbro or Takara hasn't made an official one out of this mold yet. I don't think I would have thought to use Nightbeat's head - it looks great!
That mould fits like a glove but since Punch is one hell of a sacrifice given that he's made from unobtainum, I'll jusr admire from a far. I'm curious, did you have any other figure in mind before Puch came out?
ordered the new Amazon Barricade set just to do this. I...have a feeling Hasbro is going to eventually make this guy but it's such a spot on mold..i don't know if it's worth waiting for anything else.