I say do it. Put a warning on games that need it. Done.
And you Miiverse is not mandatory people.
How well did that work out with Motion Plus?
Considering that many Consumers still think Wii U Tablet is an addon for the wii, I doubt the efficacy of this strategy.
The problem is that even with the Gamepad included with every console, Nintendo hasn't been making it a necessity for their vision of game design. None of the Marios need it, WW can be played with the pro, Pikmin 3 plays best with a Wiimote, Donkey Kong does NOTHING with its features to enchance the game and Mario Kart, Smash, and Zelda will all surely function just fine without it. Bayo 2? X? The prospects of a Wii Sports 3?
Personally, I was looking forward to software that couldn't be done without it but so far we have pretty much only Nintendoland and ZombiU, since games like Rayman and W101 could've worked just fine without it. If the console were selling fine then it wouldn't be an issue but is it really worth the mandatory inclusion driving up the cost of the console at this point with all of the big games coming out this year and Nintendo's profits continuing to suffer?