Reposting from blog. Anyway, here's my calculations.
Factor 1: According to Cinderella Master batches 1 - 3, there's a same number of Cute, Cool, and Passion idols, which is five. Since Batch 4 has 2 Passion, 2 Cute and 1 Cool idols, the next batches should have a total of 3 Cute and Passion idols each, and 4 Cool idols.
Factor 2: Before Batch #4, there were two lolis with CDs, namely Anzu and Rika. In Batch 4, there are two lolis again, Miria and Nana (she's shorter than Rika, who's a loli, so technically she counts). Assuming there'll be two lolis per category, and since there's no Cool loli yet, the future batches should have two Cool lolis. This is just an estimate- I dunno how Namco will play this part just yet.
Factor 3: Before the announcement of the 4th Cinderella Master batch, Akane, Miria, Nana, Minami and Sachiko has only one thing in common: They all have S Rares. S Rares are more or less the proof of an idol's popularity, it seems. So anyone whose gonna get a CD must have an S Rare.
Factor 4: Look back at my
previous Cinderella Master speculation post. Before Batch 3, Mio and Mizuki have yet to have their CDs, but now they do. And with the announcement of Batch 4, Nana, who also have her own personal board, now has a CD. Only two of those characters with their own boards there have yet to be announced, and is it a safe bet to say that they'll have their own CDs? I think so.
All factors considered, plus the popularity levels of characters (according to my possibly outdated list) and elimination to remove possible 'repetitions', here are my predictions, in no specific batches:
Cute: Sae, Fuei Fuei, Karin
Cool: Nao, Haruna, Chie, Koume
Passion: Aiko, Natalia, Shizuku
Well, that's my take. This is absolutely not guaranteed to be accurate, but at least it's something. What do you guys think?