I'm hesitant to say anything because I wouldn't want HD re-releases to substitute for actual NEW games in various franchises. But, if we're assuming that these would just be "extras" to flesh out the release schedule and that NEW games would still appear on Wii U for every franchise, then these are the ones that I'd buy without hesitation:
Xenoblade Chronicles HD
The Last Story HD
Super Mario 64 HD (remade with the 3D World or Galaxy or the eventual Super Mario Universe engine)
Paper Mario and the Thousand Year Door
The Legend of Zelda: Twilight Princess HD (I feel like we might get this in 2016 after the NEW Wii U Zelda in 2014 or 2015. 3DS got Ocarina 3D...then NEW A Link Between Worlds...and I STILL think it'll get Majora's Mask 3D in 2015, so then Wii U would get Wind Waker HD....NEW Wii U Zelda...and then Twilight Princess HD...3 Zeldas: 2 remakes and 1 new game for each system. Plus 2016 would be the 10-year anniversary for TP)
The Legend of Zelda: Skyward Sword HD (won't happen, but it'd be beautiful)
Kid Icarus: Uprising HD (I'd LOVE a port of that game for Wii U in HD with Wiimote pointer-controls along with the nunchuk for moving Pit...but even more I'd just love a brand new, HD Kid Icarus in the same vein as Uprising)
Upcoming Games To Get
Definite: Kirby Star Allies (Switch), Mario Tennis Aces (Switch), Fire Emblem (Switch), Yoshi (Switch), Pokemon (Switch), Kingdom Hearts 3 (PS4), Monster Hunter World (PS4)
Considering: Fe (Switch), Donkey Kong Country Tropical Freeze (Switch), The World Ends With You (Switch), Ys VIII (Switch), Street Fighter V: Arcade Edition (PS4), Kingdom Hearts 2.8 Remix (PS4), The Last Guardian (PS4), Shadow of the Colossus HD (PS4), Anthem (PS4), Shenmue 3 (PS4), WiLD (PS4)