Had a realization earlier that may lead to interesting results so I'm sharing it here. Reviewing Mii costumes in my head, I kind of realized that every pack has come with AT promotions, background characters heavily associated with a character, or both. Let me lay it out:
Joker: Morgana (taunt), Knuckles (AT), Tails (background character)
Hero: Slime (victory screen/taunt/background character), Erdrick (final smash)
Banjo: Zero (AT), Protoman (final smash)
Terry: Ryo (background character), Iori (background character), Akira (AT)
Byleth: Exe (final smash), X (final smash)
Min Min: Callie (AT), Marie (AT), Heihachi (taunt), Ninjara (final smash)
Steve: Pig (background character), Creeper (victory screen), Bomberman (AT)
Why is this significant? A couple of reasons:
-Morgana, Slime, Ninjara, and Creeper were all part of their respective characters so were made into costumes.
-Season 2 has introduced three Mii costumes specifically tied to ATs new to Ultimate.
-Capcom and Namco has been used twice now as "filler." RARE didn't have ATs so got Protoman and Zero. Fire Emblem already had two costumes in the base game (Black Knight and Chrom) so got X and Exe. ARMS already had an AT/Mii costume combo in the base so Min Min got Heihachi as well as the Squid Sisters. Minecraft obviously didn't have an AT so got Gil and Bomberman.
I want to take a moment to focus on the last one.
-Joker, Banjo, Terry, Min Min, and Steve got AT costumes. Hero didn't because Square didn't have any ATs and Byleth likely didn't because Fire Emblem's Mii costumes were in the base game. Hero didn't get an AT "filler" because Square content has only ever come with Square content. Byleth likely didn't get an AT filler because the Fighter's Pass didn't introduce any new AT Mii costumes so therefore no Tiki or Lyn. It's also notable that Byleth didn't get any background/final Smash characters because the Three House leaders and Sothis are literally his/her ALTs.
-If a company doesn't have ATs, they get characters usually associated with their stage instead and typically an AT not related to them.
This realization puts a heavy highlight on the missing four Mii costumes: Lloyd, Geno, Hunter, and Rathalos.
-Given how Capcom characters have been treated so far, Hunter and Rathalos will likely come back with a non-Capcom character.
-If Geno is a Mii costume, this further solidifies that he would have to come back with a Square character. Either way, Square is one of the remaining 4 packs; GG.
-If Lloyd is a Mii costume, this heavily suggests that he wouldn't be coming back with another Namco rep. In other words, it's basically Lloyd or nothing for a Namco rep.
-If Ryu Hayabusa really is a character, this heavily suggests that his "new" AT Mii costume will be Yuri. This potentially provides an answer to something we've been asking for almost two years now.
-Coincidentally, Mii Costume Guy mentioned Elecman so this actually makes a ton of sense if we get a Capcom rep, especially if this trend of new AT Mii costumes continues.
Circling back to Geno, this actually helps him because if Mallow really is a costume, this falls in line with what happened with Joker, Hero, Terry, Min Min, and Steve. All these characters got Mii costumes associated with their stage, taunts, victory screens, etc and the chances of Mallow being in at least one of these for Geno is extremely high.
I jotted down a ton of other notes but this is half of my thoughts on this topic and I'm trying to organize the other half better so it's not a sprawling mess.