Some thoughts on Baylan's personal quest:
Objective: He want's to end the cycle of jedi-sith-jedi-sith victories.
Means 1) He wants a grey-side victory. So he is looking for the Bendu (voiced by Tom Baker in animation), the incarnation of the grey side. This is interesting because the Bindu has a bone to pick with Thrawn, and hence could be the wild card that is needed to defeat him.
Means 2) He wants to destroy the Force all together. This would made him a version of Kreia (KotOR2). It might be significant that Darth Sion was also a character from KotOR2. If he is partially successful, managing to damage the Force, it would explain "The Force Awakens" (I didn't know it had been asleep).