It goes without saying the next saga will end with the upxoming interquel and KH4 given that the Master and Foretellers are much more powerful than Xehanort was, as well as the mystery of Subject X and Stelitza's death, The Black Box/X-Super, the other new princesses, etc. Then, there's the lingering subplot of the realm of Darkness and the hint that there *is* someone or something that exists in its depths that could be the ultimate villain of the series. Maybe the KH equivalent of Satan?
the master really did know everything i think he wants to meet sora