Super Mario: The Wonder cast minus the Toads plus Waluigi felt satisfactory enough. It's one of the factors that saved Daisy as one of the clones here too, alongside the character's general popularity. Bowser Jr. edged out Rosalina in base primarily since the former has still been pretty active in mainline, being Wonder's recurring boss fight and a deuteragonist in Bowser's Fury, among other roles. Like with Pupp's choices, Waluigi would pretty much be here since he's the one Nintendo character left that could make a Ridley or K. Rool-sized splash as a playable fighter, on top of the Assist Trophy mechanics in Ultimate already giving him a step towards functioning like a fighter (get ready, this is going to be a slightly recurring theme for the base game choices).
Extended Mario series: Yoshi is fine as is. Wario I think is fine on his own, the only real thing he needs is more side content on both a Land and Ware front. For Donkey Kong, all three veterans are very much worth keeping, and I think Dixie being a character derivative of Diddy (somewhere between Isabelle and Ken in terms of unique) would be an easy add to please people.
The Legend of Zelda: Truthfully, Sheik being on here is a very lucky inclusion, out of a mix of needing my image to be symmetrical and making sure Fire Emblem didn't outnumber Zelda once again, at least in base. Even so, Impa would still definitely be based off of Sheik's archetype here regardless of the latter being here or not, just since it'd be an opportunity to refresh that fighting style with a non-Triforce wielder. As for the other vets, I think switching around the Link and Ganondorf iterations would be interesting, letting Link return to his roots while giving Ganondorf an opportunity for further individualization from Captain Falcon. And Zelda is based off of her design from the Famicom duology, a way to change her up while still representing the oldest Zelda games.
Metroid: With Ridley on the roster now and Samus being ripe for a Dread-based reimagining, I honestly consider Zero Suit Samus to be obsolete. Dark Samus could get some individualization from normal Samus, even if it was something as simple as letting it preserve Samus's original movekit while she gets the aforementioned Dread rework.
Kirby: I used to be 50/50 on Waddle Dee's chances, but seeing that poll Swamp did with first parties moved those odds up to 70/30 in my eyes. I still feel that Dee is probably my riskiest bet on the first-party side, but with the factors surrounding him, I think I'm confident enough to not have him be part of the collective "Fan Pick" slot (more on that later).
Star Fox: Unfortunately, I can see Wolf missing base again, but I'd be much more confident on him actually returning post-launch this time, considering there was really no justification to not have him be DLC in 4 besides maybe being held off purposefully for Ultimate.
Pokemon: Holding off the Pokemon Trainer for DLC is probably a controversial move, but I do not see them splitting Charizard off again, nor can I see them leaving Mewtwo for DLC again either. Incineroar being a DLC veteran is obviously less controversial, though in my eyes the only reason he'd even come back ever is because of the wrestling fighting style, to be honest.
Fire Emblem: Marth and Ike are too popular to get rid of. Lucina is popular in her own right and will likely always be an easy reinclusion as an echo. Robin is a unique kit, and Awakening's importance to the FE series saved him from being a late veteran in my eyes. And of course, Byleth is both from the current top-selling title and is easy to bring back with how new their data is. I think they will save an unknown newcomer for DLC again since that practice has already been done two games in a row, and the Alear iron has cooled off quite a bit. Roy's also the only DLC veteran since I felt he would be the most popular one to bring back.
Animal Crossing: Both Villager and Isabelle have huge justification to say. But I am still going to dig my feet into the ground over a third character being unlikely just because I think there is fierce, fierce competition amongst first-party Nintendo characters with the 10-12 spots I think will be available.
Fit: I think it's clear that Ring Fit is carrying Wii Fit's torch, and I can see that being reflected with the Ring Fit Trainee succeeding Wii Fit Trainer in the base lineup. But I wouldn't count on Wii Fit being gone forever, more a late addition since I know that Ring Fit would have a pretty different moveset.
Xenoblade Chronicles: This is where I think Xeno will hit its cozy amount of characters this installment, with Noah and Mio as kind of a two-in-one deal, though not to the extent of being swap characters like the Aegis. There's always the chance of a fourth game's protagonist being a DLC fighter, too.
Splatoon: While I would be stoked to see Callie my beloved join the fray along with her fellow Squid Sister, I think in realistic terms, the devteam will probably be satisfied with adding Octoling as the Isabelle to Inkling's Villager and calling it a day on that front.
Everyone Else: Little Mac, Min Min, and the Ice Climbers are all characters I feel are just fine remaining as single representatives. I'm confident in keeping Olimar by himself since Oatchi always looked more like Assist Trophy material to me (but there is room for me to be wrong as I will describe soon), but I think adding Louie and the default Pikmin 4 avatar as extra alts for Olimar would be a decent compromise in that regard. Ness and Pit I feel will have to go solo on launch day, but Lucas and Palutena would definitely be among the DLC veteran lineup to satiate fans of those two. I think Dark Pit is probably done, since out of all the Echo Fighters I imagine he is still the least popular, especially with Daisy and Dark Samus both being well-received new Echoes in the last installment. Officer Howard from Astral Chain is the one brand new series I am fully confident in being added in base, especially since the game has been completely under Nintendo's thumb for a while now.
Retro: All three of the previous retro characters are fan favorites at this point and all unique additions to the cast, I can't see any of them being gone. After the dud that was Piranha Plant, I imagine that the next "surprise" pick will be more along the lines of the retro trio--obviously I can't say for 100% certain who it would be, but I see potential in Diskun as a mix between Game & Watch's reference-heavy moveset and ROB's design as a living version of a Nintendo product.
The Nintendo Placeholders: While this may seem like a copout, there are certain elements I'm not fully clear on predicting, or can't properly predict currently. The two "Future Release" placeholders present on the "with DLC" roster are meant for Nintendo characters that'll debut on their next hardware, whether they're stars of a new IP or a new installment in an existing IP. As for the "Fan Pick" placeholder present on both versions, that simply is a catch-all slot that could go to a good handful of Nintendo characters that I could see get in, but I'm not fully confident in unlike the other newcomers I placed.
There's quite a few characters that I think can take the spot, and I'll list them along with their pros and cons.
-Isaac: Popular fan choice, would add a new series to the lineup, can be modelled from Ultimate AT; but is from a particularly dormant series to the point he wasn't even in 4's AT lineup
-Krystal: Popular fan choice, was considered for Brawl, can be modelled from Ultimate AT; but hasn't been used in recent Star Fox titles on top of Star Fox itself not seeing any activity since Zero and the Starlink collab
-Takamaru: Has legacy for Nintendo and has some fan demand, can be modelled from Ultimate AT; but doesn't have as much push as other choices compounded by his game not being international for a good while
-Lyn and Tiki: Popular characters in series to the point of being ATs; would have to contend with a likely-tightened FE lineup and would likely be ignored in favor of a new face
-Starfy: Has some fan demand, would be simple to program, can be modelled from Ultimate AT, has some revitalized interest with NSO rerelease; but I'm convinced Sakurai has it out for the guy at this point
-Tom Nook: I've stood thoroughly corrected on things from a fan demand standpoint; but I could still see the Smash team skip over him in favor of more outwardly-unique fighters
-Oatchi: Has some fan demand and would give Pikmin a second character; but as I've said, could easily be given an AT role instead
-Someone from Rhythm Heaven: Still a semi-popular Nintendo series without a character yet, and signs point towards a character being planned for Smash 4; but the series has not seen a new installment in quite a while and there is always the possibility that the Smash team cannot settle on a character or concept in time
-Ayumi: Has a decent fan movement, was mentioned during Melee development, her series has seen a full revival; but said full revival could have come a bit too late for project plan development, and some of the other choices could win out in terms of fan demand
Mii Fighters: Considering signs point towards Nintendo's next system being primarily a Switch evolution, I imagine the Miis will be kept around for legacy software, and by extension will remain in Smash for the time being.
SEGA: Sonic hasn't missed a game and there's no chance he'll miss one now. Bayonetta is still comfortably under Nintendo's thumb so I see no justification for removing her either. I see Shadow getting added as some sot of clone primarily due to how much SEGA has been pushing the character again, primarily with the Fearless Year of Shadow event and the products associated with it, and also because he'd probably be the easiest choice to develop amongst Sonic's cast. Joining these three as DLC would be Arle from Puyo Puyo, who has long legacy and popularity in Japan and a now-sizable fanbase in other territories, along with the current series director saying he'd be OK with putting her in Smash if given the opportunity. There'd also be a DLC slot for an Atlus character--while my template implies a brand new face, I won't rule out the possibility of Joker being a returning DLC character, either. It all depends on if Atlus wants to promote something new or if they still want to milk P5 at that point in the future.
Capcom: Joining the returning three from Ultimate would be Zero. Zero pretty much has everything going for him in my eyes--he's had sizable demand, he's a popular character in general, he has an AT in Ultimate to work off from, and he'd explicitly bring in what would basically be a new series' worth of content with him, considering how different MMX and MMZ are compared to the Classic games. There's a few other characters from Capcom I could see being added as DLC, but I'm currently going with Dante since (IIRC) his costume in Ultimate was a response to the requests for him that people made during Ultimate's DLC cycle.
Konami: Snake and Simon return. I didn't really indicate this, but I've been pushing for Richter and a couple other Belmonts like Trevor and Julius to get rolled into Simon as alts for him. Bomberman would be the other new base third-party, having popularity, legacy and existing AT data to his name not unlike Zero, on top of the deluxe costume he got in Ultimate that I felt was an acknowledgement of how much people wanted him to be playable. I already listed my reasoning for Tako earlier, and I will quickly paste the quote again here:
"Tako is my shot in the dark prediction for DLC, being a feasible representative of Konami's expansive STG catalogue. It pretty much comes down to process of elimination--he's in over TwinBee because Parodius is an extension of Gradius, which is essentially the "heart" of Konami's shooting-game body, and he's in over the Vic Viper because the latter is a static ship--it's not even given TwinBee or Opa-Opa-esque features in Parodius--and a cartoon octopus would naturally be easier for a developer like Sakurai to envision "dancing in his mind", so to speak, while also still being able to replicate elements of Gradius gameplay thanks to his loadout being based off one of the weapon sets in Gradius II. Basically, it's my answer to the question of putting in a space shooter character in Smash, like how Arle solves the puzzle game character problem."
Namco: Pac-Man would come back for base game. I could see Kazuya being held off for DLC just so Namco can entice the players who liked him in Ultimate, on top of the added incentive of modelling him after his Tekken 8 appearance.
Square-Enix: Cloud and Hero would come back for base game. Like with Kazuya above, I think Sephiroth and Sora will be held back as DLC on purpose to entice players into paying, as sucky as that would be. Joining those two in DLC would be Crono, who I chose both because of the character's importance regarding the height of Nintendo and Square's relationship back in the day, and because he was listed on the "Square Seven" rumor that circulated during Ultimate, which I believe is all but factual information about things regarding Smash and SE internally.
Microsoft: Considering Microsoft's continued amiable relationship with Nintendo at this point in time, I expect things to be smooth with Smash as well. I see both the bear-and-bird duo and Steve returning for base--and for DLC, Microsoft currently holds two big Ultimate-era requests under their fort, being Doomguy and Crash, and considering how easily Sakurai and co. got Banjo, I imagine Crash will get added in without too much trouble, and they'd probably work out something in regards to Doomguy, considering he also got a costume in Ultimate in response to fan demand.
Other companies: I fully expect Terry to return and as a base character, considering SNK's hands-off approach with their content in Smash paying off rather nicely all things considered. New companies I see getting characters are as follows:
-Koei-Tecmo is the frontrunner for a brand new company in the form of Ryu Hayabusa's addition, as the legendary ninja's name was pretty common during Ultimate speculation, and it would be far from difficult to translate him into Smash's context. While a lot of that may have been spurred on because of fake leaks, I think the means are irrelevant to the ends here, and it's an addition I see most people being content with.
-ArcSys is another good contender, and I see Sol Badguy being their representative considering Smash's fighting game character streak so far. The main reason I believe ArcSys to have their foot in the door is thanks to the River City/Kunio spirit event for Ultimate, which to me is a sign that the company has some interest in getting a slice of that Smash pie.
-Falcom is a long-standing company with a good few franchises under their belt, and I have a gut feeling that Adol from Ys is in the cards, just because that seems just like the kind of pick I can see Sakurai getting to add that bewilders a lot of people and makes sense in hindsight. I'll admit this is another shot in the dark of mine overall, however.
-Finally, there's FromSoft, who I think is very likely to get represented with the Tarnished from Elden Ring. That game's popularity cannot be overstated, on top of being a part of From's long-running chain of action games. If Elden Ring gets a version on Nintendo's next system, I'd say he's as good as in from a DLC standpoint.
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