I want you to think about one thing for just a minute: Frickin' Matilda from The Professional is in this film. Jules from Pulp Fiction is in this film. What you're seeing as "awful" casting is awful directing. How at sea do you think Natalie Portman has to be to deliver a performance like that? You think the chick from Black Swan couldn't be Leia's mom? I think there wasn't any clear direction giving anyone in the entire series anything to hang their hats on.
Maybe a good actor can find their way even without direction, a good script, real sets or chemistry with cgi? -okay, you're right. Seriously, you are. Portman is a great actress and she probably could have been great with the right material and guidance. That said, I thought Sam Jackson, an actor I admire in other works was clearly a wrong choice. There are others too -Jimmy Smits etc. But your point isn't lost in me.
Completely agree. 100%. I was trying to find something redeeming and landed on Ewan Mcregor, who I thought did the best with the least, of anyone. Then my train of thought went to casting but you are right, it's at the bottom of a long list of failings.