The philosophy behind the Wii U is a mixture between Wii, DS, XBOX and PlayStation. Maybe that's the problem... They tried to appeal to all groups of gamers instead of focussing on specific groups. It doesn't have a clear identity.
Droppping the GamePad would be disastrous. Even most games with Pro-Controller or Wiimote support need a GamePad to start. Third parties probably won't patch most of the already released games.
Nintendo could patch NSMBU to start without the GamePad, but games like Pikmin 3, The Wonderful 101 or 3D World would have to be reworked.
Games like ZombiU, Lego City Undercover, Nintendo Land, Wii Party U, Game & Wario would be completely incompatible. It's impossible to patch them.
2DS is compatible with all 3DS games. How should they market a cheaper Wii U with a Pro-Controller that can play only around 20% of the Wii U library at it's launch and cuts features of it's games?
