Zahgnol is actually already in the game though - it appears as a Wanted target during Temple battlecraft levequests in Coerthas Western Highlands.

But I can definitely get behind having the Festival of the Hunt in FFXIV though (Ul'dah especially would be a perfect location for it!). It would have to be a special instanced event though (maybe part of the main scenario, just like FFIX's version was), otherwise it would just become yet another mass-player zerg-rush. And yes, full remix of Hunter's Chance is kind of mandatory as well.