The box theory, for what its worth, does indeed have a pattern as others have said.
It groups characters in bunches of 9 and then goes on to the next group. There are 0 flaws in that logic as people have made designs that show it.
The only time this pattern breaks is Palutena-Corrin, where Ryu is located, and Vergeben, arguably our most accurrate leaker to date, has said Ken's in as a Ryu Echo.
Putting 2 and 2 together from there isn't hard.
A pattern is something that repeats. But this doesn't. It breaks in the row you mentioned, which is why I said our first thought shouldn't be: KEN! Our first thought should be "Maybe there isn't a pattern." But why is it 9 characters each time except the last row? Because you can flip a coin a hundred times and coincidentally they could all be heads. Seeing patterns that aren't actually there is another cognitive bias we should be aware of and make us more skeptical.
The question of why would they be in sets of 9, while there are only 6 slots per row, causing a discontinuous jump in the middle of each row, has no satisfactory explanation. Is it possible the box will ship like that, with Ken, Isabelle, and Incineroar? Sure, but it seems really unlikely.
And of course the Box theory could possibly fail even if that's the finalized artwork, as there could be characters announced after it ships. Every time I look at it, more and more problems arise.
Reasons why the CoroCoro news might be wrong? Sakurai talking about the number of stages *seemed* definitive, and it could be a misprint. That's it really. I really don't think the two are comparable. I recognize my bias, I see the information that conflicts with my prior assumptions, and I believe I could be excited about this while having the caveat that it might be a misprint. Not hypocritical, as far as I can tell.
CoroCoro >>> Music Theory > Box Theory >>>>> Chairs
Do I have to repeat myself?
You guys do know that Box theory and 108 stages don't have to contradict each other right?
Just like in philosophical circles, there's soft Box theory, where the box doesn't ship with every character on it, and hard box theory, where it does. CoroCoro debunks hard box theory, unless all 8 stages are returning stages/new stages for veterans, announced characters, Ken/Isabelle. But that's boring*.
*yes, this is called self-deprecating humor, I realize this is not actual evidence