I imagine magitek armor will work in the same sense as choco raising. It might just be a pvp thing only where people can tweak and customize their magitek armor and then face off against one another with their unique setups. The parts would come from all crafts and those parts would determine the skillsets you can use with your magitek armor as well as HP/MP and the amount of TP they can gain.

It would be really difficult to setup magitek armor as a class or a plain PVE concept in itself unless they only made it for one gimmicky event and then barely went back to it since they then would either only have access to said magitek armor concept during said instance. They could just turn magitek armor in a unique pvp game which would also allow those who don't have a DoM/W to be involved in a pvp concept if they don't want to lv said classes.