IMO Nintendo has quite a lot of games they could bring out for Wii U, like a big Super Mario game on par with 64 and Galaxy (I know people have said that 3D Land is like that, but I don't think it went far enough, or had the same level of wow factor), they could bring back Blast Corps, make a big screen edition of Pilot Wings.
An open world Pokemon game would no doubt be a system seller and greatly appeal to the target audience of the system. Pokemon will no doubt move a lot of Amiibo figures and big game like that could have several DLC expansions or new releases like the handheld games, adding new Pokemon, sections to the world, etc.
I always thought a Kingdom Hearts style adventure, with a new lead character that interacts with Nintendo's characters would be great, basically a big RPG and huge fantasy world set in a complete Nintendo universe would be a huge system seller.
Bringing back Wave Race would be awesome too IMO.
Maybe put some more focus on franchises that aren't as well covered like F-Zero, Metroid, Starfox.
These comments from Miyamoto could mean that Nintendo had to build game engines that are more flexible for the current gen hardware, now they may have those, so that would drastically speed up the development process, given how automated a lot of these engines are now and Nintendo must re-use a lot of the same assets across the Smash, MK and many of their franchises, which speeds things up too.
It's really not that hard for Nintendo to have a lot of content that could move units, they just need to plan better, start development of a lot of projects early in the generation, that way maybe you have a lighter 1st or 2nd year, but when the competition starts to heat up from the your rivals (whether Nintendo likes it or not Sony and Microsoft are their rivals as they're console makes, operating in the console market) you have a large stream of games to deliver in later years.
