The thing about supporting WTF characters... It goes against the whole idea of having a WTF character in the first place if there's no shock-value to it. In other words, all this talk of supporting folks like Sheriff and Diskun is rather silly when we'd already see them coming.
Game & Watch, having no basis for us to guess his appearance.
R.O.B., with everyone believing he was out of the game when smaller R.O.B.s were confirmed as enemies.
Wii Fit Trainer, when literally nobody expected her to be one of the first reveals, or a WTF character to be non-retro, or a reveal at all in the first place, actually.
They each came to the roster with impact, the whole point of adding a WTF character. Adding a second type of character like that, to be honest, feels pointless when people are already expecting one. People were blindsided before, but the community is ready for a second whammy, meaning it'll just be a disappointment more than a surprise. I guess you could compare it to if a friend tries to make you flinch by throwing his fist right into your face. It works the first time, sure, but if he tries it again too soon, your reaction won't have as much pay off in that you're ready for it.
So Sheriff, Diskun, and N64 Logo supporters alike. Good for you, you're the ones that aren't going to flinch when/if they're revealed. I'll just be sitting here saying "meh" when/if they are instead.