I'm reading the OP, and this is what I see:
Where are you reading "easier to develop for"? While I hope that's true, how do we know this isn't just the new leadership telling everyone in the company "We need a new 3D Mario every year. We need a new Zelda every two years." etc
We know the handheld teams and console teams came together... last year? Two years ago? I always figured that was a move for the next platform in order to produce games quicker.
Assuming the thing is cross compatible with the handheld, this isn't as bad as it sounds. Instead of 3D Land in 2011 and 3D World in 2013, we get two 3D Marios for NX. At least that's how I'm hoping it'll go.
The philosophy of needing a zelda game every 2 years gave us majora's mask, so i'm ok with that.
But, it's as you say in the end, I think the assumption is that instead of staggering releases on console > handheld > console, etc, it's just ALL CONSOLE with a good portion of it also going to handheld.
I'd love if they just sat down and kept using the Zelda U engine to crank out a new zelda game every 2-3 years for a bit while also giving us top-down ALBW spin-offs every other year.