Besides Waluigi which I have already mentioned, I have the following I would love to see:
- Slippy Toad: I think Slippy is the most unique of the Star Fox crew, so him having a playable chance allowed more diversification among the Star Fox characters, even more so than Wolf, who many people view as being similar to Fox despite being somewhat different. Besides, Slippy's got Star Fox Guard to fall back on for material. (Not related to Toad from Super Mario Bros.)
- Tingle: Another unique Zelda character, and one that's appears several times. He's even got his own games, so in case the arbitrary "must have your own game" rule ever comes up, Tingle's got them.
- Mallo: The Pushmo playable character will bring Sumo moves to the playfield, for he's a sumo-based character in case one wants to have sumo fighters in Smash
- Dillon: The character has an incredible character design, as are his friends that include Nomad the sniper squid (predating Splatoon's Inklings). Due to that, a Smash popularity boost is what is needed for Dillon to become well-known.
- Style Savvy lady: Style Savvy is a strange fit due to the focus on fashion, but it would be an eccentric choice.
- Wonder Red: Let's bring the other notable new Nintendo property from Wii U as a new fighter! (in case you can't tell, the new Nintendo property I alluded to is Splatoon)
- Chibi-Robo: Although it might be it for this miniature automaton to get new games, Chibi-Robo is still a charming robot who does things, and now we know his plug can be weaponised!
- Spring Man: It's likely that ARMS will only be included as a downloadable character, but if there's one character that is the face of the newest franchise, it's Spring Man.
- Sukapon: Sukapon was off limits back in the Melee days due to legal issues, but with Sukapon no longer being in legal purgatory and is now Nintendo-based, we could have our very first limbless fighter! (assuming Rayman didn't get in first)
- Commander Video: The only indie character that had a Smash trophy in Smash 4, Commander Video's a largely Nintendo-centric franchise due to the bit.Trip series starting on WiiWare and Runner3 being Switch exclusive. He has the entire bit.Trip history to base his moves around.
- Shantae: I wouldn't mind Shantae getting in, given her origins (started on Game Boy Colour). I am not sure the original game is owned by the very company that created the property since there's no Virtual Console version of the original yet.
Thank you for reading.