"Disappointment" is just not a word I can associate with DKC:TF. It's a remarkable game that sold well for the userbase it had. It also has one of the best soundtracks of the 8th gen.
DKC:TF catered extremely well to hardcore Nintendo fanbase whereas Splatoon caters to the more common tastes of gamers today. DKC:TF is a challenging 2D platformer with high production value. That type of game just doesn't excite a broad audience of people. The 2D platformers with real mass appeal tend to have a much lower difficulty curve and emphasize ease-of-play and familiarity (New Super Mario Bros) over challenge and innovation.
Splatoon has often been mentioned as "Nintendo's answer to CoD" - and in a way, it kinda is. Up until Splatoon, nearly every other publisher except Nintendo has been after some kind of online shooter that can create a persistent community of gamers that will buy the series in the future. Nintendo just happened to do that better than most publishers. Big surprise.
I predict NX launches in 2017 - not 2016
