NES - amazing console that practically birthed the console market in Japan and revitalized it in America. Lots of great 'hidden gem' action games, beyond the obvious.
SNES - the GOAT. Best 1st party games, best RPG lineup, technically proficient with amazing sound.
N64 - this was a big disappointment coming after the SNES. My tastes have always been RPG heavy, and the utter lack of RPGs on the N64 really damaged it in my eyes. When Nintendo announced their "dream team" of people like Acclaim... and not Capcom/Konami/Square/Enix, that's when I knew something was amiss. The blurry ass textures and fog didn't help matters much, nor did the sound quality or the unorthodox controller.
GC - a step up from the N64 in terms of 3rd party games and library variety, but aside from Melee, had the weakest first party games. Cute industrial design, though.
Wii - a system with a ton of promise that all seemed to go out the window once cheap waggle became the order of the day. Was expecting it to get more Japanese 3rd party support that never materialized. Some of the first party games were great, but even then they got waggle forced in. The Virtual Console was the real highlight of the system for me. A legal way to pick up so many fantastic retro games, including a ton of obscurities and some games never before released in the US (Monster World IV and Sin and Punishment).
Wii U - a disaster of a console, with a confusing message and a clunky ass tablet. But some of the game releases were pretty good, Mario 3D Land in particular. Nintendo should have just scrapped the tablet and released this back in 2010 as "Wii HD" or "Wii 2" with a cross-gen Skyward Sword and Xenoblade... or they should have skipped this system entirely and released the Switch a few years earlier.
Switch - still a bit too early to say, but the concept is what I've been wanting from Nintendo for years, and its first year brought the big guns (Zelda/Splatoon/Mario). Also looks to be the first Nintendo console with a good RPG library since the SNES, especially since it seems to consolidate the games usually released on handhelds (which were always strong RPG wise). Wish it had a Virtual Console, though.
GB - the original, though truthfully its library is really dated. There are a few good games (Link's Awakening, Seiken 1, Gargoyle's Quest), but most of it is cheap puzzle games or highly compromised takes on 8 bit console gaming.
Virtual Boy - headache inducing, from the few games I've played on it. An interesting collector's novelty, but easily the worst thing Nintendo's ever done.
GBC - don't really have much experience with this, but it seems like a stop gap release that was quickly rendered obsolete by the GBA. The DQ ports were cool, though.
GBA - I had pretty high expectations for this, but it's got its share of flaws. The terrible screen in the first model, awful sound quality, and lack of face buttons kept the system from reaching the potential it should have. The SP had such great industrial design and that's where I jumped in on the console. Some nice niche releases, and some decent SNES ports, but Nintendo first party was pretty weak apart from the Metroid games.
DS - And for this, I had extremely low expectations, but it ended up surprising me. At first, it seemed like a gimmick platform, but the 3rd party support was massive, the RPG library was ridiculously large (though never quite hitting the highs of say, the SNES/PS1/PS2), there were tons of creative and niche games. Probably the best Nintendo handheld.
3DS - I shut off the 3D gimmick, and technically doesn't seem much of a step up from the original DS. The blurry screen and muddy textures a lot of games have make it seem that way. There's a decent library of games, that I haven't explored nearly enough as I should.