Zelda Twilight Princess HD
I'm surprised no one has posted here about the new version. I read a couple of fairly favorable reviews (Washington Post, Wired) and finally decided to take the plunge.
I never finished the original version. I got stuck following the wagons through the field when I couldn't aim the Wiimote correctly to shoot arrows at the bad guys.
Anyway, I hardly use the Wii U anymore (switched over to PS4 due to the dearth of games coming out for Wii U), but I downloaded Twilight Princess, and like the new version so far. They did a good job upconverting, and the beauty of the graphics now shines through. Gameplay functionality is very smooth. I don't miss the Wiimote yet, but I haven't gotten very far in the game yet. So far, using the gamepad works very well.