Where was this thread when Smash 4 was released? That was the game that had lackluster single player content. Smash Tour and Master/Crazy Orders were definitely not my cup of tea. Classic Mode was also a disappointment.
As for Ultimate, The omission of Stadium Mode is unfortunate, but everything else is fantastic. I clocked nearly 30 hours in World of Light, and each character having their own route in Classic Mode (which is the best version in the series, imo) is awesome.