I personally found the Wii U kinda disappointing, it had some great games like 3D World, Splatoon, Smash bros. But it felt like there were so many continuations of old series like Smash and Kart, and very few new ideas, or if they were new they weren't great, like Star Fox.
I also feel like games such as Captain Toad and DKTF were bad ideas because they were so limited in scope, not a lot of mp options or modes. Nintendo needed games like Splatoon in the first year, and games with much grander scope to them. There was hardly anything remotely close to Mario Galaxy on the Wii U.
I hope that with the Switch we can see Nintendo gearing up and bringing the big guns with bigger scope games, new IPs, local and online mp, and new ideas. The Wii U felt like it could have been so much more, a console who's potential was cut short.
Discussion started at here by MrOdacious