Not sure how much of a programming issue it is, but using weapon coffers as an example, how would a White Mage or Black Mage go about with getting either option? And as minor as it is, people would probably call you out for trolling the party using two-handed weapons, because you're effectively giving up the possibility of damage mitigation through blocking (tryharding) for vanity.

Incidentally, would the one hander and shield combo remain unique for White Mages and Black Mages? Why not the other healers and casters?

I personally don't miss the wonky stages of vanilla A Realm Reborn gearing - as a poor noob, being unable to use gear upgrades because of the silliness that was the Darklight Cowl and such was beyond annoying.