Things we can start guessing at thanks to this + other stuff-
We now know for certain there are 3 styles per character. Depending on how much that changes characters(given scorps examples it seems significant enough) we're looking at a roster with 24 unique characters and 72 actual playstyles. This is good from a variety standpoint, but at the same time I worry a lot about balance here. The first few months are going to be filled with claims of "broken" or "trash", and it may take a bit for the meta to settle, but a big part of how well this game does long term will depend on how many of these "styles" are REAL choices, not just a way for casuals to see different movesets.
Now assuming this is the correct character select screen count, and not including things like random and DLC slots, some guesswork-
We've got 6 already with 2 classic, 2 new, and maybe 2 "sorta new" characters(depends on how related to khan this guy is).
At the very least I don't think we'll be seeing sonya or cage given that Cassie is a thing. I'm guessing her styles will allow her to play more like one or the other. This would likely also include characters related to their story, so Jax and Kano would be higher on my "won't make it" list.
Ninja's- We've got the two "no duh" choices in sub and scorp, so no surprises there. I am mildly worried that scorps "summon a dude to mess people up" style means we won't be seeing noob. Concept art has been floating around for ermac, and going off what i've seen, if you forced me to guess I'd say the characters slot two to the right of sub zero is him(The silhouette looks like the pointed cowl from the concept art), so he's probably a safe bet. Beyond that it's hard to say. My only other thought is that bug lady sorta fills the "part human part animal" niche that reptile had, so he may not be coming back. Given all this, Noob has more plot significance than smoke, so if I had to guess on one more returning ninja it'd be him. Rain doesn't even get mentioned because as fun as he may or may not be, he just doesn't strike me as important enough to get a slot.
Robots- it's interesting to note that sub zero is a thing. This is supposed to take place after MK9, and the scorpion/sub thing was sorta resolved. Dead sub became noob, and living sub became a robot....so who the hell is this guy? Their grudge was never solved I think(scorp doesn't know right?)...so yeah...this is odd. Either way the fact that he's human doesn't speak well for any of the cyborg characters making a return( i mean it's a minor thing because human sub zero will be in EVERY mk, but I don't see any silhouettes that scream robot either)
Kung la0/liu kang- Should still be dead? I expect someone to fill their shoes somehow, as these two are almost sub/scorp levels of main character for the MK universe. The characters themselves may not appear.
Female ninja's- It doesn't seem like an obvious choice either way. I don't think we'll see all of them, and if that's the case Kitana is the clear winner plot importance wise.
Shinnok/quan chi- Both appearing would make sense. They were essentially teased as the big villains at the end of MK9, so not having at least one of them playable would be surprising. That said with the chance to have new characters and add to the cast/write some new plot, I doubt they'd just want to only use only them as big villains. My guess is that in some way shinnok/quan win, and this 25 years after is related to their rule somehow, and the hell that results. Still MK plots are anything but simple....so there's a lot of chance they wind up playing a small part. Even then I'd imagine one of them getting in.
MK4 vibe- Obviously MK9 was the retelling and remix of the old MK's, and with shinnok as a possible villain + various art choices, I'm getting a very MK4 era vibe here. MK4 very much was a "old playstyles new skins + new guys" sort of affair, and that seems to be what they want here. Personally the two most memorable characters from that era were quan and shinnok, who i've already mentioned. Other possibles include(new to mk4 only)-
Fujin- maybe? I don't think they ever did a great job with him, but he fills the "god amongst fighters" role well if they axe raiden, and maybe now they'll actually make him interesting?
Jarek- Part of the jax/sonya thing...so no.
Kai- I seem to recall him being pretty hated and terrible? I dunno, maybe, but I doubt it. He was the "new liu Kang" in a way that no one seemed to care about?
Meat- god I hope not.. Or maybe just as an easter egg since a random character skin doesn't take that long. Actual moveset and plot time would probably annoy me to no end.
Reiko- Like fujin the guy had some potential that they never really used. He seems much to minor to dedicate a character slot, but if it's supposed to fill that MK4 void they might use him in some way?
Tanya- Maybe? I'd personally doubt it, but of all the new comers that hit 4 she was one of the few that at least sorta was fleshed out and caught on?
and that's really it for new faces to MK4.
Shang/Shao- Likely dead/deafeted? again if this is the "Retelling of mk4" then their lack of involvement would make some sense. The one khan character throws a wrench in that somewhat.
Other MK1-3 era characters- I already mentioned the robots, but I also don't have high hopes for stryker, kabal, sheeva, barraka, or anyone else i'm forgetting. They've sort of served their purpose plot wise, so if this is a moving forward thing we might see some cassie like versions of one or two of them, but ultimately I wouldn't say it looks good.
Deadly alliance era- I'm going to guess no. Personally I think a lot of these designs were some of the worst that they've ever done, and objectively it doesn't make a whole lot of sense to start dragging them and their whole mess into this. It would be interesting to see some of them get the "lets make you not suck" treatment some members got in MK9, but I don't think this will be that game.
TL;DR-Game will be to MK4 what MK9 was to 1-3 but with more branching out. I'd put money on ermac, less money on shinnok/quan chi and Kitana, a buck on Fujin/Reiko for our returns and then maybe one other "spiritual" successor for the kangs. That leaves 12 slots for new characters + or - a few although I'd guess at least 3-5 of those will be other "spiritual" successors, although I couldn't guess for who.
Edit- on silhouettes: Other than the ermac guess I can only say that I don't see anything that marks obvious returns, and some things that maybe point at no shows(raiden would be pretty damn easy to spot if he's got his hat for example, and very few of these seem to be sporting any head gear). Only other obvious one is what looks like Fedora guy, but I'd bet quite a bit it's not going to be freddy.
Please NRS I want in MKX the all ninja females be clothed ONE FUKEING TIME!!!!