Yeah, the changes are immense. Every single character has made huge changes to their personality. You can see that the basics of their personality are there, but they have been warped into the "war-like" version. Jake's responsibility has become a type of leadership where he does what's necessary and is willing to make sacrifices. Rachel's recklessness has led to her accepting the dark side of herself and using it as a weapon. Ax has gone from cadet to warrior. Cassie has learned to make moral sacrifices and use her intuition for manipulation. Marco has gone from a smart kid with an eye for strategy to cold and calculating, knowing what has to be done and not fretting with the emotions of it. And Tobias....well, Tobias has learned that he can be loved, that there is a possible future for him...and then he has it all ripped away from him.
Huge changes. Life-altering (world-altering, really) changes.
