I don't actually care about the argument itself, but you guys can't say these things as fact. There's no way to truely know who buys or doesn't buy what and why.

The current PS4/X1 userbase is not families buying for their kids, it's 18-40 year old males buying for themselves based on hype.

A $299 price is a barrier to much of MK's audience.

That's debatable ... 

With this year being very likely the peak for the WII U, I'm surprised that the WII U will go on to sell similar numbers like last year. With the WII U currently tallying up to 2 million units with latest shipment data suggesting an overtrack of 300K units, the WII U has so far sold 1.7 million units this year. If we can take a look at an otpimistic case that the WII U will sale about 50% of it's units for the holdiays that will come to around a total of 3.5 million units which is roughly a 10% increase from last year's sales of 3.2 million units. 

At the end of the year the WII U should come to have sold 8.8 million units and the next year is the WII U's only decent year left since Nintendo will have played every cards they can get their hands on. With another optimistic expectation the WII U should reach 11 million units by then but how exactly is Nintendo supposed to sell 3 million more units when the wells are dried up ? 

And what exactly is the userbase of the WII U made out of ? Whatever you think the WII U base consists of I can assure that most of it is NOT families either ... 

Who exactly is MK's audience this time around ? 

I don't see how. They're implementing DLC for the long term to continue sales for games like MK8, Smash, and HW, have highly anticipated releases in Zelda, X, Mario, and Retro's secret game, continue to push the amiibo, and have recently announced that they're workin more with third parties to speed development of game assets, second party endeavors, and using previously created assets/engines to speed development time (SM3DW > Captain Toad, MK8 > F-Zero/DKR?).

As of their recent Q&A it seems Nintendo's recent restructuring was their set up to put their back into pushing the Wii U.

I'm actually agreeing with you there, Wii U is not currently selling to families. Sales of Skylanders and co show cheaper consoles like Wii and 360 do better with this crowd.

MK has a very broad appeal, but it isn't hitting the full range at the moment cos it's on a console that's not priced for parents shopping for their kids.

You can't be serious that $300 is an issue for parents, right ? That's like less than fraction of their annual earnings! That's a VERY affordable price no matter how anyone looks at it ... 

It's an issue when last gen consoles are much cheaper and offer similar games. Parents shopping for their kids don't care so much about specs the way the hardcore do. Cheaper is better for this audience.

In that case then don't ever expect the families to catch on to MK8 since the PS360 is cheaper ...