I think Ed Boon mentioned in Kabal's Biokard that they're looking for characters that are deceptively disabled: Kabal, Kenshi and now we can Jax because apparently an other feel-good disabled character getting implants and getting back at the guys who disabled him was much more interesting that a guy whose sense of duty and responsibility is so strong that he'd risk his life getting experimental bionic implants to help him save Earthrealm.
Anyway, speaking of design cues, I'd love to see Sub Zero's frozen arms again, I thought that it was by far one of the coolest (Har-Har-Har) design elements in MK's History.