I believe that what needed to be done is already in effect. Now it's time to play the waiting game.
The Wii U was too expensive. No one predicted the PS4's launch price before E3. In order to counteract Sony's trump card, Nintendo wisely chose to market the Wii U much like the Wii before it, as a dramatically cheaper alternative. But this marketing has proven to be a double edged sword. Because Nintendo is no longer following its blue ocean strategy, instead placing heavy emphasis on bringing "core" gaming experiences back to its home console, this generation is more comparable to the 6th generation (GCN, PS2, Xbox). Nintendo lost there because the Gamecube had no key features distinguishing it from the rest even though the Gamecube rapidly dropped to the very agreeable $100 pricepoint.
Nintendo needs to make more of an effort to convince gamers why they need to purchase games for the Wii U instead of the alternative platforms. Although the other consoles are tablet optimized, the GamePad is the Wii U's primary control output. Early games like Nintendo Land, ZombiU, and even ports like Batman Arkham City did a good job of underlining this feature. Players could "be" Link or Batman by carefully aiming arrows or maneuvering the Batarang. Fighting off hordes of zombies was more engrossing because shaking the GamePad to loosen an attacking foe made you feel like you were actually living the moment.
At the start of every generation, people are quick to say that the most powerful system will demolish the competition, yet the past three generations have proven the opposite true. The most commercially successful systems of those generations, the PS1, PS2, and Wii also had the weakest hardware. Instead, they tried to offer something for everyone. If Nintendo can continue to convince developers to make Wii U versions of popular games while also encouraging third parties to bring software only the Wii U can bring to the table, the Wii U can still perform as well as its predecessor despite the rocky start.