1.
Waluigi is playable.
Speaks for itself. And just to note, I've wanted him waaaaaaay before he became a meme. I legitimately love Waluigi as a character ever since Mario Strikers. He is the best Mario character of all time.
2.
Mewtwo partially reanimated:
2b. Mewtwo's down tilt changes into a psychic(or non-tail whip ability) attack, and not the weird tail sweep. He has way too many tail whips. He also needs a new shielding animation, I imagine it looking like this(reference to pkmn first movie):
And if the outstretched arms are a problem, him simply crossing his arms would be phenomenal as well. His current shielding animation just looks bad, and not stoic enough for Mewtwo. It's a bit too cowardly and tryhardy for Mewtwo. Even a simple forward facing palm is better. Probably any other pose is better honestly.
To me, Mewtwo needs to look like it isn't taking much effort for him to do the attacks he does(with exceptions). This gives the impression and feel that he is powerful(which he is), but also is part of his character. This is especially true for his psychic-based attacks. If he were to have, say, Thunder Punch, it would be okay for him to visibly put some effort into it.
Just replacing his animations with psychic/telekinetic based animations(in order from greatest to least in necessity):
[Down tilt]
Side-Tilt
Down-Throw
Up-Tilt
Up-Air
Just these changes alone would probably make me happy enough to consider it the Ultimate Smash(though that would be my personal bias talking). That's how bad I want these changes(I want this more than Spyro and Sora, that should say enough).
3.
Spyro as a newcomer.
That would be absolutely insane; all throughout my Smash life I never even dreamed Spyro could be in the game(even though I wanted him), but that seems possible today. I would relish the chance to beat up Ridley as the superior purple dragon.
3b. A very close second is
Sora. Kingdom Hearts is very near and dear to me.
4.
Story Mode at the level of Subspace Emissary from Brawl or greater.
I feel like having no story mode at all would be a big hole in the "Ultimate" title. So many people want it to make a return(probably with accompanying cutscenes). My little brothers always tell me how much they want to see it in the next game, and I certainly don't disagree with them. Having a story mode, with a storyline, with all these characters, with cutscenes would be absolutely incredible. This is the shining reason Brawl was as great and classic as it was(non-competitvely).
5.
Conserve momentum into jump.
No idea why it was taken out. So natural and fun. Always loved this about Melee, and it only makes sense. Super Mario even has it, the most casual game of all time.
6.
Good shield stun and hitstun comparable to Melee, or slightly less(if too much).
7.
Melee-like dash dancing.
I always liked this mechanic, but conversely wondered about it's total implications. This is a perfect example of something very intuitive for all to perform but adding depth at the same time. It makes sense and looks cool. Some people say this is a "non-committal" option, but I just see it as a way to mix-up your aggression and movement. What would be so bad about implementing this? Doesn't this promote offense? I'm open to being corrected here.
8.
Strong attacks pushing shielding opponents off of platforms.
More intuitive reward for aggression, also just a really fun mechanic IMO.
9.
Character-specific special smash options.
I want to play as giant stamina DK and fight 3 other normalized characters.
10.
Iron-Man/All-Star Character stock mode:
Smash Tour had it at the end, Project M has it, put it in already. I want to play as different characters for each stock in a tag-team battle. This really should already be in.
11.
Wavelanding with less lag(snapping to platforms will be very quick and efficient).
They can keep the non-sliding off the edge property, but I don't care much either way. This is really the only popular Melee mechanic I would like, or seems to be reasonable enough to add. This is because it seems intuitive and easy enough to implement and perform without total disregard to casual audience. I just don't think wavedashing should be implemented as an off-shoot of airdodging diagonally into the ground. That's bad design imo. That is also too many buttons for most(and before you assume, yes I personally find wavedashing to be easy to perform and I only play Smash 4). A more simple button press to do so would be preferable(if needed), but I question the need for wavedashing wholesale. We already have many options out of dash, and microspacing options can probably be implemented in a more intuitive way(if not already in the game). Let's not destroy our hands.
12.
Ganondorf further decloned/reanimated.
He needs to use more dark magic and less awkward non-sword physicals. He fights like he's a martial artist, not a wielder of the Triforce of Power. The following should be changed with some magic attacks/sword moves(or non-tryhard physicals that excude power over technique):
Up-air(looks a little better in Ultimate, but still doesn't fit him. Magic is better)
Back-Throw??(It was very dumb in Smash 4, if it's the same it needs to change to some magic attack. Havent seen it in Ultimate)
Up-Tilt(Why does he have to do a full split rivaling Wii Fit Trainer? Just use magic and not such a SUPER EXTRA yoga pose beforehand)
Neutral-Air(Too tryhard/Captain Falcon/martial artsy, just have him do like a double magic blast, or double sword-slash or something)
Down-Tilt
Back-air
Down-Air
13.
Ability to change controls without needing to exit the CSS.
Nobody likes having to exit out of the character select screen and waiting for the other to fix their controls. Let's cut this out entirely. Hbox made the same suggestion.
14.
Better replay system.
Need to pause, fast forward, rewind, trim options. Easier to export file and share as well.
15.
Revamped stage creator.
So much potential in the Wii U version, just a tad more options would make it even greater.
16.
Combos should be even more prevalent than they are in Smash 4.
Goes without saying, hopefully.
17.
Untechable Footstool
Unlikely to change, but I'd rather more combos than less. Not a deal breaker, but I will miss these combos. I thought footstool combos were some of the coolest things to see in Smash 4.
#BetterNerfGreninja
Have at it Sakurai, I think that's most of it.