SIGNED!
I don't own a Wii U or plan to buy one, but the NGC controller was by far the best controller ever made by Nintendo. Wii remote was a gimmick 90% of the time, only maximizing its potential in certain first/second party games like Metroid Prime 3. Wii U tablet looks neat but IMO would have been better as a stand alone product (replacing the Wii U console and going for a straight up gaming tablet, merge the console and handheld markets and make a KILLING). There is also the problem with wireless connectivity. Wii remote is a pain in the ass to deal with at tournaments and you really need to provide people with a wired option of some sort. Wii U pro is basically a 360 rip off, and even though the 360 controller is the best ever made IMO, it's not so great for some games, particularly fighters and even more particularly the Smash series.
If anything, Nintendo could release an adapter to plug the NGC into a USB port on the Wii U. Cheap, solves problems, people can continue to use their NGC controllers they already own. I don't expect them to do much of anything considering the state of the Wii U sales, but Nintendo really needs to pull their head out of the ground and actually listen to their fans for a change. They are so stuck in their ways and refuse to admit when they lost and it will only end with them going the way of Sega. Just watch.