You're the JLC expert, so please add your input... A slim Reverso case like the 1931 Reverso. A special dial, maybe a historical dial, or a blue dial (a blue model already exists but not in a slim case). An 822 caliber, but maybe with some special movement finishing like some polished anglage, special Breguet hairspring, and/or swan neck. Of course, they can't make it too complex or else servicing the watch will be difficult. A collection of straps with quick release spring bars and the new deployant buckle that can be removed without any tools.