I can think of two already.
One, I am curious about
Spoiler
the "Quaille Wars" (wondering if that is a conflict with aliens?)
And two, if other alien races will join the Rage War, like for instance, the Arcturians. I remember James A. Moore or one of the authors said "there were plans" for the Arcturians and this pleases me greatly.
Speaking of which, I wonder if the Human Sphere covers Arcturian space as well.