I don't believe that was because the Wii U was powerful relative to it's competition, but rather because Nintendo had no software to define the Wii U at launch and justify its gamepad.  Just like the Gamecube, the Wii U didn't know what it was and it lacked that one killer app that Nintendo needs to catch its hardware on fire close to launch.

The success of Ninendo consoles always depends on Nintendo's 1st Party software and the ability of that software to define the console.  The N64 did this with Maio 64 and as a result, the console creamed its competition (Sega and even Sony) right up until the end of 1998.  NES had Super Mario Bros, the Game Boy had Tetris and later Pokemon, The DS had the Brain Age craze, the Wii had Wii Sports.  Whenever a Nintendo console has failed it is generally because Nintendo hasn't had the right 1st party software (near launch) to explain to people the messaging of what that console is supposed to be.  The GCN and Wii U were two examples of this. 

I don't believe power will necessarily have much of an impact on the success of the NX.  It's going to come down to whether Nintendo can couple the NX with the perfect piece of software at launch that gives everybody that "ah-hah" moment.  Attracting 3rd parties will come as a result of this.

The sad reality of best case scenerio for NX multiplats.... 

True, but there really is no need for three practically identical devices either. So which way do you go....

The home console has to be at least as powerful as the PS4, otherwise no third party support. I think PS4 and XBox One will still be supported for a few years, but we don't know if the PS4 Neo userbase might eventually grow big enough for all the developers to abandon the current generation.

I don't think it will be anywhere near as powerful as the PS4Neo, though, except if Nintendo does the trick with cloud computing (they have a patent, remember). Nintendo will not try to win the console war with mere power, they want to be innovative and I think they want to make an affordable device.

Stronger than PS4, equal to or SLIGHTLY weaker than NEO.

The Wii U was stronger then Ps3/x360.

Both console got alot games the wii u didnt got even after launch.

Like: Metal gear Solid 5, GTA 5, COD Advanced Warfare, Battlefield 5, Battlefield Hardline, Dragon Age Inquisition, Fifa 15, Fifa 16, Fifa 14, Crysis 3, Shadow of Mordor, NBA/MAdden games, Bioshock Infinite, Dark Souls 2, Destiny, Need for Speed Rivals, far Cry 4 and much more.

All released on ps3/xbox360 after wii u launch but not on wii u. Strong hardware wont change nintendos relationship with third partys.

I'm not saying that strong hardware will guarantee third party support. I am just saying that weak hardware which makes it difficult to port PS4/XBone games to NX will guarantee that there won't be any relevant third party support.

It may be more powerful than the PS4/X1, but I'm thinking it'll be more of a N64 vs Dreamcast difference rather than a N64 vs PS2 difference.

Not exactly.

AMD's successor to the consoles archaic and slow Jaguar CPU's, aka. Puma... Can operate at powerlevels of 3.8w with 128 GCN cores and 4x x86 1.6ghz cores.
At 16/14nm, you could halve that power again or double the hardware.

Intel has had mobile SoC's that have been able to beat out it's ARM competitors in many cases for years.

As for Price, you have a point.

Lol im not an hardware expert but i highly doubt you could achieve ps4 performance (graphics and cpu whise) with 3,8 wattage. 

It would be amazing if possible, but i really cant believe it.