Personally i think ALL TABLETS weather it be apple, android or windows, are reaching a point of diminishing returns. The novelty of using a tablet has worn off, and outside of the standard better camera/screen/specs, different sizes, there is only so much you can do with them.
At the end of the day, a tablet is never ever going to truly replace a laptop or desktop machine for some things, and a desktop/laptop is never going to do other things as well as a tablet and i don't care how much you try to combine them with products like the surface line or what ever, some things like in-depth encoding and writing are always just going to work better on a keyboard and mouse, while more artistic things like drawing, or certain types of games and media consumption, will work better on a tablet.
At the end of the day, what more can you really do with a tablet anyway? Sans the addition of 3d touch or some other form of haptic feedback on a tablet where you can physically change the texture and feedback of the screen itself on some level, i as of now can't see a major breakthrough revountary change for the platform anytime soon.
I honestly think when apple put out the iPad and iPhone, there core design and function was so well thought out and refined (yes there were other touch screen tablets and phones out there beforehand ) that it set the bar so far ahead that people unrealistically expect them to do that with every revision of the product every single year and you simply can't just do that!
It really is a case of a once in a decade or even lifetime breakthrough, and apple does that more then any other company and the expectation for them to do that on a constant bases is outright unrealistic. Some years they refine the product greatly, other years..not so much.
Honestly and realistically though how much thinner lighter and faster can these things get? At what point does the screen and camera resolution become so high, so detailed, that the human eye can't no longer perceive the difference from one to the next?
Short of them adding holographs or some sort of crazy science fiction like thing, what more can you get out of a tablet platform?
and for people to say the pro is a disappointment, fine i can see why some people for there own needs would come to that conclusion..but what more do u really want in a mass produced product?