The Wii U is actually the best console of this generation for some people due to its decent lineup. Nintendo games are rarely bad, despite being iterative.
Maybe, but that's mostly because apart from Forza 5 and Bloodborne Sony/MS exclusives of this generation suck. Dreamcast had strong exclusives too, NBA 2K was born on that console. Also Shenmue.
Exclusives these days are iterations of some long going series. There isn't a new and exciting game on any of consoles, that is reserved for PC these days.
Mario games are great but I'm not 12 anymore. For multiplatforms Wii U sucks because it is very weak hardware wise.