I think if done, Castle Grayskull should not be broke up into pieces! Despite all the bickering people would do about not getting that piece from Matty. There would always be some complaining when you get two pieces and they don't connected properly! So just stick with selling it as a whole!
I would like to see Grayskull to look similar to the way it does on Scareglow's reliquary. But have it close up similar to how the 200X version did.