Heihachi's costume being missing is pretty suspect. Either Bamco is getting another rep (I'd bet you ANYTHING it would be Lloyd or Heihachi at this point) or something weird is going on.
Whatever the case, today proved that B-K were, indeed, the big outliers in Fighter Packs and the Mii costumes with each. So far, they're literally the only one to go with a bunch of Mii costumes unrelated to them.
Joker? SEGA costumes.
Hero? Square Enix costumess (mainly DQ and stuff tangentially related to DQ).
Terry? SNK costumes and fighting game representation.
The cases I could see Geno's outfit returning is with one of these conditions:
1) A weird outlier condition like B-K, which would likely only be with an uncooperative or rival company a la Microsoft. This is highly unlikely.
2) An RPG rep of some kind coming with the outfits. I'd look at Lloyd Irving for this possibility. Geno to ToS feels like such a far cry from Virtua Fighter to SNK's fighting games, however, so I 'unno.
3) Another Square rep that is not Geno gets in.
4) We get Mii packs that are NOT connected to any character releases. We do not yet have any kind of precedent for this, so this is also pretty unlikely for now.
5) Geno is in; therefore, we party like it's 1999.
The things I'd look out for are 2, 3, and obviously, 5. I'd say of those three, strictly speaking on FP, we'd have to look for 2. If we get Lloyd, he might come with Geno's costume and the Mallow, Smithy, and Chocobo hats/costumes. It's a lot, so I'd call it pretty unlikely that he'd get all that SE material with him, but since they're also from JRPGs (just as Akira/Jacky are also from fighting games a la Terry), it is a slim possibility. Outside of the Fighter's Pass, if we get more Mii costumes with further characters (highly likely, imo), we'd have to look for either Geno or another SE rep. If Mii packs are done when the pass is done, then we'll either see the last pack having Mallow and such in it with Geno as a separate, playable fighter, or they'll all be in with Geno's outfit included and no playable Geno.
There's a loooot of ways this could go tbh.