This is an academic concern, since I don't particularly enjoy the genre. Still, the advantages of the Wii U controller with regards to RPGs are pretty obvious, even putting aside any potential innovations.
Maps and Inventory. They aren't sexy, but they are pretty useful, and having a persistent inventory would be very handy, particularly in a Borderlands/Diablo-type of game. But other parts of the game, like the battle system, could also be simplified and streamlined. Want to use a potion in the middle of battle? Tap the icon. Want to issue real-time orders to your party members? Tap the icon. Want to cast a spell without going though menus and submenus. Why, tap the icon!
Imagine playing a lightning-fast RPG that isn't overly simplified. Having a secondary display would allow that. And, of course, for the grindfests, you could play remotely on the screen. (I would question why you're still even playing at that point, but whatever.)
I'm going to answer my own question by cutting most WRPGs out of the equation (at least until the PS4/720 launch), since Western companies seem to focus on the most powerful hardware. But I think there's a good chance that 'big' JRPGs could migrate to the platform. Or
should migrate. Then again, I think the Wiimote offered some cool enhancements to the RPG, like pointer-based NPC interaction, but that hasn't gone very far.
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