I almost feel as though the world of Wheel of Time might be too big to do up properly, but since this is unlimited resource land, that could be cool to see. The One Power would be easy to do as a game mechanic, and there are plenty of potential villains and cities and places to explore. My only concern might be the feel of the world. It's a pretty orderly world, all said. Unless I'm forgetting, we don't really see bandit groups or dangerous roads or dangerous wildlife or anything of that sort. It's a world where people move about and trade and travel and there aren't many everyday dangers that a player could confront and solve and defeat. Main story stuff with the Dark One's forces, maybe the Seanchan too, could be very good, but it might be difficult to come up with enough side quest fodder to fill the whole world.