Not to mention that if ROB is a character it would reveal that one icon on the Dojo.
But if that was it for the roster I wouldn't mind.
We already got Pit, Wario and Sonic after years of begging, we have three cool gimmick characters in Olimar, Pokemon Trainer and ZS Samus, the Kirby universe gets a better representation and even Snake could be fun to play as.
Not to mention that the veterans have been upgraded so they may play even better than before.
So really, how could you ask for more?
If we get even more, fine, but what we have right now is more than enough.