I didnt think Keaton was a great Batman, but he was decent. He at least established a character.
Intelligent: Keaton's batman cracked the Joker's "Death by makeup" code. He also uncovers that Max Shrek (Christopher Walken) was lying about the need for more energy for Gotham.
Obsessive: He struggles to have a relationship with Kim Basinger because he cant stop being who he is. In the second flim, he obsessed over the Penguin while the penguin pretended to be a poor orphan trying to find his parents. Alfred calls him out on it and Batman dismisses his criticism.
Frightening: In the opening scene of Batman, one thug is dangled over a roof-top and then allowed to let go. Batman scares the out of him and then tells him to "Tell all your friends about me". He likes to haunt his enemies they way they haunt him. This is WHY he wears the gothic costume.
Clever: Batman uses the Penguins audio against him in the Penguins big speech: I played this city like a harp from !!
Now...how did Bale/Nolan convey those same characteristics?