I agree with all of the points basically. There wasn't much agonising over my choice at the time and we intend to get another console as well (though if had to choose only one, it would be the Wii U). The release of Pikmin 3 and Zelda WWHD had made me think it was about time to get a Wii U, and when Super Mario 3D World came out it sealed the deal, with the future promise of a Super Smash Bros, Zelda and Mario Kart title enough to sell me on a system. Local multiplayer was really important for me as well, PS4 and Xbox One so far appear to have basically zero appeal on that front so far outside of Halo. Value wise I was able to get the wind Waker Bundle with Super Mario 3D World and a Pro controller for around £300, so that's immediate great local multiplayer and a wonderful Zelda game (one which I hadn't played that much having only borrowed the original to complete it). For less than £400 total we added Pikmin 3, Rayman Legends and another controller,and with the Wii Motion Plus controller from Skyward sword remaining compatible that gives 4 useful controllers for if several people are round and we wanted to play local multiplayer (Gampad + Pro controller are enough for the serious gaming). The other new consoles had just released at the time - for £400 I think at best I would have ended up with the console, a single controller and a single launch title, none of which particularly interested me, and it would be the only game I could play (and depending on the game I would only get the most out of it after paying for the online service). Value-wise there was no contest between Wii U and the other consoles, though obviously that is different now depending on your taste in games.
Backwards compatibility wasn't really a major reason for me getting a Wii U (I still have my Wii set up as well, though funnily enough that is only for its own backwards compatibility functionality so that I can play Gamecube games...), but it is a bit of a turn off for the other two consoles. I will probably be getting an Xbox One at some point, but that point would probably already have occurred if I knew I could just replace our Xbox 360 in the living room with it. There is limited space for primary consoles at the TV (and the fact that the Xbox One is so bulky doesn't help here), and while Halo MCC being released definitely makes replacing the 360 with the One an easier choice for me (assuming the multiplayer will eventually function properly), we have a ton of Xbox 360 games that my girlfriend especially would still like to play. Right now (especially with the new Assassin's Creed, which would have probably have been a "system seller" for my girlfriend, being a buggy mess) it almost doesn't seem worth it to relegate the 360 to the other room alongside consoles like the PS2 and The Dreamcast, considering the games we can currently play on it compared to what we would feasibly get as initial games on the Xbox One.
So yeah, value and local multiplayer experience are big positives for me choosing the Wii U too. And of course I want to support Nintendo as I want to continue to be able to get their games and consoles in the future. But really games are the key.
Edit: And just in case it's somehow not clear, those are my thoughts on why the Wii U "won the console war in my house", i.e. why it was the (first) one I decided to buy. I am not predicting that the Wii U will sell the most...
Additional Edit: It's quite unfortunate and ironic that the two games this year that would have been the bankable "must-haves" to sell the Xbox One to our household (Halo Collection for me and Assassin's Creed for my girlfriend) were both botched at launch.