I was thinking about it earlier and realized that if we add in the remaining 3 of the original 12 and the Gematsu leak, we'll be at 39, from there, if we add the "Big 4 Villains" Namely Mewtwo, Ridley, K. Rool, and Ganondorf as well as Meta Knight, Lucas, Wario, Wolf, and Falco, we'll be at 48 characters with a Random Button, with cuts of G&W, R.O.B., Ice Climbers, Snake, Ivysaur, and Squirtle.
This would lead to a 3 x 12 Row x Column arrangement with the expected random button being by itself on the bottom row. Since I feel that such a size is plausible, and that we may not get all of the Brawl Vets back (as I listed), I too feel that Ridley's chances are better now than ever.