I woke up this morning wanting an explanation as to the reasoning for these changes, so thank you for that.
I have only been able to do a few arena battles so far. The things that upset me the most are the changes to Yoda. He is the reason that I invested in this game. I put the effort/resources in to get him to 7* and added him to my squad. Before the update, the AI used him badly which made me an easy target. I accepted that, because it's Yoda. Now after the update he's just bad.
I look forward to the challenge of GW and the class challenges and will post a review if I have anything productive to add.
After now trying my galactic war and the challenges, I just don't care if I finish them. They take so long and some of it is me making mistakes but this is just too much at once. I enjoy figuring out new ways to do things but this change has made me just not care.