Duck Hunt would be a great game to include in that micro-console, but there are some technical issues that are apparently difficult for Nintendo to resolve within the resource and time constraints.
The NES was released back in the era where CRT TVs were the norm and the HDTV weren't commercially sold. Every version of Duck Hunt beside the Wii U one is only playable with any CRT TV, thanks to the latter's near-instantaneous refresh rate and the way the game registers fired shots.
Every time you pull the NES Zapper trigger, the game will a display a screen on the TV with black background and one or two large white squares for a single frame (which is about 1/60 second). These white squares represent where the ducks actually are and provide information to the NES Zapper whether you were actually pointing at them or not, which was done during that frame.
Since HDTVs don't benefit from the near-instantaneous refresh rate, the NES Zapper will never be able to land a hit on any target. Therefore, Duck Hunt is unplayable with any HDTV, unless you're using the Wii U VC port of it.