As someone who was really disappointed in the very first trailer for 3D World, and who just bought it two days ago and has been playing it non-stop since, I can assure you that saying it's "crap compared to Galaxy" is a huge lie. I won't say it's better than either of the Galaxy games (I think the gameplay in 3D World is far better than Galaxy 1, but Galaxy 1 had a wonderful storyline and atmosphere to make up for it's shortcomings in gameplay, while 3D World doesn't have a storyline, and the atmospheric levels aren't plentiful), but it's very close to the Galaxy games. If it had online play, it would be just as good. But even as it is, 3D World still turned out fantastic, and it's better than anything the PS4 and Xbox One are putting out (the Xbox One is just terrible right now, so I likely won't touch it for a long time. I have a PS4, but it's library is very mediocre right now. Only exciting game on the shelves right now is Killzone Shadow Fall).
Also Luigi's Mansion 2 is miles better than the original and you're being blatantly nostalgic if you think it isn't. It just handles way better, there is a lot more to do, Luigi's personality shines bright like a diamond in it, and it's got online multiplayer. And it's portable.
As for the Wii U, it's not a failed system at all. It's merely a struggling one, and it's not the first Nintendo has had. Heck, the 3DS's situation was just as bad in it's first year. Now look at it. It's selling like hotcakes.