Oh so many. Off the top of my head:
We need a new F-Zero. GX was amazing, it's pretty much my favorite game of all time, it was a crime they didn't release a sequel on the Wii, the Wii U is more than capable of handling it though. Think of all the amazing things they could do: HD courses! Online play with up to 30 racers! It would be amazing! They need to do this!
A Tales of Symphonia remake. It was the game that got me into the Tales series its still my favorite in the series and one of my favorite games of all time, a remake for the Wii U would be awesome (I'd be cool with a 3DS remake as well)
Another entry in the Baten Kaitos series. I can't lie to you people anymore, the GameCube was pretty much my favorite system of all time, and this (along with the previous two games) was the reason. Origins was amazing, th battle system was fascinating, the characters were engaing, the world was one of the most interesting I've seen in any game, right next to Xenoblade Chronicle's world.
On a different note an Elder Scrolls game for the Wii U would be kinda cool, I know it's not likely but unlike the Wii the Wii U could definitely handle one, it'd be awesome to see an Elder Scrolls game on a Nintendo system. Maybe a remake of Morrowind or Arena.
I can't think of much else... maybe a sequel to The World Ends With You. It's a little premature but The Last Story and Xenoblade Chronicles definitely deserve sequels and there's no better place for them than the Wii U! And that's about it.