How many games in a row are people gonna try to invent a center slot for a boss? There are 22 spots in the square. We know 22 characters. And the were even the same 22 characters that were in a leak from months ago. Yet this is still somehow a mystery to people. It's just baffling.
Also those side dots get covered up by both the color selection UI and the CaS UI which would be really inconvenient if you were trying to pick your character while someone else was picking their outfit. So I wouldn't expect them to be cramming a DLC character in there. The layout will have to change when the rest of the season pass eventually comes out.
Because Inferno in the top left corner is ridiculous. Why would the embodiment of chaos go inbetween the two heroic figures, Xianghua and Siegfried? At least put Azwel there, since he is a self-proclaimed hero, even if he's misguided and actually evil, or at least seems to be that way. The slot positioning in general could have been done better, yes, but putting Inferno on the far left side would be the biggest blunder of all, if that's where he goes. It goes against the entire thematic premise that they established, while putting him inbetween Kilik and Grøh, Sophitia and Geralt, is so much more poetic that it makes perfect sense for him to go there.
About the side slots, I was expecting them to adjust the UI when those characters were announced, or they could also swivel them down and make a sixth row of five, in the long run, once the other three DLC characters come out, in a best case scenario. But Tekken 7 reorganized the screen, so it's likely that SoulCalibur VI can and will reorganize the screen in some way once all the DLC characters are out.
If the top left character isn't an unlockable character, likely Edge Master, possibly Hwang, then them leaving a corner empty like that for potentially a month or three is also a really dumb move. The side slots being empty is far less conspicuous. The only other possibility might could be if Cassandra is the second DLC character, also available at launch, and she goes in that corner. Only then would I believe that all three blank slots are DLC.