Easiest choice ever, lol.
On the topic of Bale vs Affleck here. One reason Bale automatically is superior to Affleck for me is...imagine a younger Affleck in Batman Begins. I'm talking circa-Daredevil Affleck. It ain't the same movie. I would argue the whole thing wouldn't have worked. Rebooting Batman in the mid 00s with Affleck would've just been ill-advised.
Bale was able to craft a Bruce Wayne characterization you could believe in from the ground up, and take you on a journey with him where you don't even care that he's not in the suit.
IMO, Affleck benefitted from all the work Bale had put into making Batman a credible cinematic character that audiences believed in, stood on that foundation, and then just played an older and meaner Bruce/Batman. He did that well enough, but it annoys me that so many fans say Affleck was the best now. Just because of a more comic book-y suit and a cool fight scene that his stunt double performed. Seriously, you remove those two elements and not nearly as many people would say that. Bale is becoming criminally underrated for the work he did in these films, and so much of Begins rested squarely on his shoulders.