Surprised how you're still a fan of Nintendo without 3rd party games like those 

Move to PS or PC instead if I were you

But if you only could pick one...?

Gamecube

Absolutely, no doubt, hands down... The WiiU. I really wanted to like the idea of the gamepad. But from the moment I bought it, I wanted to turn it off to play on the TV, because the second screen looked worse and distracted me. Even the sound is not timed well with the TV. And not only it was not possible to turn it off, but also it lasted just 3 hours. I instantly thought "ok, this is not well designed", and it's the first time that happens to me, regarding a Nintendo product.
Nintendo has always been a synonym of quality to me, I buy their consoles because I know they are going to last for Many years, I still have my Nes and Snes working! But the WiiU felt different, like a cheaper piece of hardware, more like a product from Microsoft or Sony tbh. Anyway, I don't know if I'm buying the switch, not sold on the concept at all, I'll have to see how it turns out. What I've seen up to now, looks a bit wiiu-ish, with some terrible mistakes corrected, like playing on a TV with the controller without any other disturbing hardware on, breaking the atmosphere.

At least the Wii U is going to win something...

I have a Xbox and a PC now. Wouldn't have had to do that if Nintendo could get 3rd party titles. Is it really so wrong to wish that Nintendo get their shit together and make a home console with enough power to run 3rd party titles? I don't get why I'm always being told to GTFO because I want Nintendo to get with the times.

Tie between the NES and the Wii. Both had the least amount of aamzing games imo.

People actually voted for SNES & Gamecube? how? Not that many but how can anyone view that as the worst nintendo home consoles?

Easily WiiU.

I thought they wouldn't come with something that would bore me more than Gamecube did, but WiiU did and then some. It's just not a good system. Just a handful of worthwhile games, even for a Nintendo enthousiast, and besides maybe Mario Kart (surprisingly) none that are really a step forward of that bring new and inspired things. There was no progress in WiiU. And then ofcourse the objective reasons; droughts, mediocre system with mediocre features. Now it will get even worse because practically everything is going to be ported to Switch, which basically makes WiiU a pointless, throwaway system nobody really needs. There was some potential, I thought so before release at least, but Nintendo dropped the ball hard on this one.

For the record:

N64 > SNES = NES >> Wii >> GC >> WiiU

N64 is the best, the whole 5th gen was the best, the whole last part of the '90s/first few years of the '00s were the Golden Age. Everything was a classic, too many new ideas to count. And yes, the N64 controller was also the best. Then I guess SNES, which had awesome games, but I probably like NES, because it has awesome games, just as much as SNES. Wii had plenty of cool stuff, new stuff with new ideas, and it got me back into console gaming so it's after the classic consoles. GC after Wii, a few good games, but not that many. System itself was solid, so it wins easily over WiiU, which has almost nothing going for it sadly.

It was hard to decide between Gamecube and Wii-U but Wii-U was even worse.