If it's the ZHP guy, much like all his games, I will buy it day 1.
His latest PS3 one had a great plot but...really poor dungeon crawling unfortunately. ZHP's was excellent and I still say that game was a 9 outta 10, extraordinarily under-rated.
I enjoy games that play around with concepts or ideas. Like that RPG about the boss with a Trillion life, Makai Shin Trillion.
Or like how in Soul Sacrifice you can literally fight the last boss whenever you want, even immediately after starting the game.
An RPG about life after the great evil is defeated could end up amusing. Buncha animes based on that premise though and only a handful were any good.