These gameplay changes sound really cool. It's too bad they won't stick after the event is over.
The crystarium only affects the FFXIII regions anyway. And there is a story reason why Wol can use it.
They have lot of gameplay variations on a per region/event basis. Didn't you guys get the PuzzDra collaboration? That was the first one with gameplay variation (combos). The second FFVIIR collaboration, Fatal Calling, will have materia. Some of the later story chapters have element influence. The DQ collaboration has DQ jobs with their own levels, independent from your deck level.
Also, since some people still aren't aware, Toriyama has been directing Mobius from the beginning.