If the old rumors from people in the know still hold up, the launch Mario game is going to be an open world sandbox game with a mix of multiple styles that will be inside this world. IDK if that means it's Mario GTA. Karts instead of cars, powerups instead of weapons, etc. But any way they went with it, Miyamoto has shown that he is still coming up with new great ideas. No Miyamoto, no Nintendo.
Also, Nintendo doesn't need a lot of third party games to be successful. They have a huge first party list of franchises that continues to grow. I have a PS4 and XBO, but I play the Wii-U the most, because it's not a couch exclusive system. PC is PC, and it's silly to have 3 systems that do the same things IMO. Until AR/VR is clean, and not just tech demos and unpolished features that make early adopters justify the purchases, Nintendo has a huge opening to break through.
Plus, they have so much money in the bank, and so many IPs, that they can flop another 2 systems and still come out okay. I just don't think they can flop this. Especially since they will pretty much recoup the hardware R&D at launch by using the tegra platform, then recoup the price offset a few months after. Basically impossible to flop. Something tiny like 8 million units would break them even for the life of the hardware.