Here is an interesting article about the Wii U pad use:
"It’s no secret that the Wii U GamePad isn’t being utilized to its fullest potential. For such a major part of the console, its use has been fairly limited, making few appearances as a focal point in either third- or first-party titles. This is a disappointment on many levels; the unused possibilities of such a device are endless. Yet, it hasn’t been completely ignored, with developers often still making small use of it. These small uses add up and, though there should undoubtedly be more thorough use of the device, what we have seen so far has actually improved games quite a bit."