edited: If I at least knew how many simultaneous helpers are used in PotS' Rare Akuma, it could solve my question.I let him fight for a couple of matches and the most helpers he ever had during that time was 8, which only happens if he pushes the aerial fireballs.
But I guess the answer is just to not use more of them than what you need at a given moment, and as few permanent ones as possible (Rare Akuma has 2). Also since it seems that you only need them for one move, it's ok to push the limit a bit if needed, since any eventual slowdown would be restricted to said move.
That is... assuming going over 32 didn't even cross your mind, because that would be insane.
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