The NES is hands down the best. It had the most original content by far of any console. The following IP were all created on the NES/Famicom:
Super Mario Bros.
The Legend of Zelda
Advance Wars (Famicom Wars)
Those are some of the biggest franchises in gaming and they were all created on one system. Although in order to appreciate the NES, a person probably had to live through it. Someone looking back will not think that the first Final Fantasy or Metroid or Metal Gear is the best in the series. But many of the games that came later were making gradual improvements and iterations upon the originals. Were the later versions better? Yes (usually), but they were standing on the shoulders of giants.
When it comes to original content no other system can beat the NES. Many people may remember the first time they played GTA3 or Final Fantasy 7 or Minecraft or Dark Souls. On the NES those types of games were coming out all of the time. Every year had several hot new games that felt like nothing you'd ever played before. That it is why it is the best system ever created.
There are different ways to define best console or games. Appreciating the invention of franchises and genres is one.
But better games meaning a better console is a common definition.
I enjoy Super Metroid more than Metroid
Megaman X more than Megaman
Final Fantasy 6 more than Final Fantasy 1
ALTTP more than Zelda 1
Turtles in Time more than TMNT 2
(Although the original Punch Out being a rare exception, where I liked the NES version over the SNES sequel.)
For me, the SNES was the best Nintendo console because I enjoyed the games on it the most.
Aside from the ones I mentioned above:
Secret of Mana
A ton of fighting games (Dragon Ball, Fatal Fury, Art of Fighting, Street Fighter)
Donkey Kong Country
It had an abundance of third party games, on top of its great first party lineup, and that made it my favorite Nintendo home console.
It is very much a matter of taste. I think, because I lived through this era, that I actually like harder games. So the difficulty of say, Metroid makes Super Metroid seem better to most, but I actually like Metroid better. Also some of these NES games relied on things like an instruction manual or other inserts to be playable (like Zelda). If you try playing the game now without these tools it doesn't feel quite right.
So, I actually do like the NES games better in probably more instances than you, but also, at it's time it was far more amazing than any other console in its respective time. For me Mario 3, Zelda, Metroid, Mega Man 2 and Punch Out were the best in the series. The other franchises I mentioned have better entries on later consoles. But even considering all that. It would be nice to have a modern console with this level of originality.