If the NX is a tablet which produces 720p graphics while portable or used in the VR headset but when fitted to the dock a fan system in the dock allows it to run faster for 1080p TV hdmi graphics then perhaps later a NX 1080p tablet could be produced that can do 1080p without additonal cooling based on a smaller fabrication process for portable use and still remain 100% compatible. I guess it will have a SD card slot for upgradable storage.
To be honest though you don't buy Nintendo hardware for the spec normally as its generally terrible for the price. It's about the game experience. Far less pressure for Nintendo to offer upgrades.
The NX as a 3 way portable, virtual reality and home console system offers good portable performance, average to low VR experience and low home console performance. It's all about having 3 ways to play the same games. You don't need state of the art hardware for some virtual reality mario kart.
