If they are smart, which they are not, they would hold back any Metroid, Mario, Zelda, Donkey Kong, Kid Icarus, Megaman, whatever else - games, and develop all those to launch THE SAME DAY as their new system.
Quite literally every popular game available at launch of the new system - and watch the sales go nuts.
They cannot release a system and expect great results when it takes 4 years to launch not even 5?? of their main staple 1st party titles which is Super Mario World 3D, Mario Kart, Smash Brothers... Shit that's 3. (I know I am forgetting a few) But still... That's outright ridiculous.
Hold the NX system launch and with that launch the following all on the same day:
New Donkey Kong Country NX
Metroid NX
Zelda NX
Mario NX
Megaman
Contra 1st person shooter
Starfox NX
Kid Icarus NX
Launch all those titles at the same time. Otherwise they may as well just cash in their chips and have their last Sushi dinner before going out like dishonorable/defeated Samauri.