So, just predictions and hopes here?
Toga Marth and Shirtless Lin-
I mean ....
Bandana Dee rounds off the Kirby cast well
Geno or Paper Mario for Mario RPGs
Isaac gets in revives Golden Sun and encourages Nintendo to activate the 7 Nintenballs and revive Advance Wars, Custom Robo, Hotel Dusk, and more.
Advance Wars and Custom Robo get a character
Sakurai picks a retro character from the cast and makes a new game for them (Ice Climber : Uphiking pls)
Tekken, Super Robot Wars, Tales of, Soul Calibur, and Dark Souls music for Namco please
Yakuza cameo for Sega (or Shenmue)
Beat Em up stage with Urban Champion, Final Fight, Streets of Rage, River City Ransom, and Double Dragon cameos
A Fire Emblem character from Judgral or Magvel makes an appearance
SF music isn't just SFII, MM music isn't just NES MM, FF music isn't just 2 FF7 songs (I would love a MvC2 song or SFIII song)
Obviously 99% of these things won't happen, but still, you said hopes lol