I am overall content with the roster. I do feel that the fans should have received more, such as Ridley and Mewtwo and even Isaac. I may seem bias in saying King K. Rool should be there, but then again, I'm really not... The most significant villain of each franchise should hands-down be in this game.
Overall, I summarise this roster as being a pretty bloody great roster, particularly in the uniqueness department, but Sakurai ignoring his fans and sending out too many mixed messages and curve balls stopped it from being a pipe-dream in my opinion. This is mostly because, admittedly, I feel Sakurai was cruel in dealing with Ridley (there is still the DLC theory, but don't expect anything), and should have just dis-confirmed Ridley when he showed Pyrosphere then and there instead of egging Ridley's fan-base on. I feel that if he had done that, the hostile reactions and numerous threads of hate / disappointment wouldn't be so numerous.
The minor disappointment I felt with the roster (gross lack of Donkey Kong content, this cannot be argued) is for the most part overshadowed however by the thought and creativity put into not only some of the veteran characters, but also characters such as Palutena, Bowser Jr., Shulk, Duck Hunt Duo, Mega Man, the Villager and many more.
For those who are new to Smash for this instalment, I hope they learned the lesson out of this that some of us learned years ago... That is, Sakurai cannot be tabbed or predicted, and that pretending to be able to do so will only get you burned.